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INSECT  PESTS 


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FARM,  GAEDEN  AND  ORCHARD 


BY 

E.   DWIGHT  SANDERSON 

DEAN    OF   THE   COLLEGE  OF  AGPICULTURE,    WEST   VIRGINIA  UNIVERSITY 
DIRECTOR  WEST   VIRGINIA   AGRICULTURAL    EXPERIMENT    STATION 


FIRST    EDITION 
TOTAL   ISSUE,    EIGHT   THOUSAND 


NEW  YORK 

JOHN  WILEY  &  SONS,  Inc. 
London;    CHAPMAN    &    HALL,    Limited 

X915 


Copyright,  1912, 

BY 

E.   DWIGHT  SANDERSON 


PRESS   OF 

BRAUNWORTH    &    CO. 

BOOK    MANUFACTURERS 

BROOKLYN,    N.    Y. 


(La  Mxj  W\U 


PREFACE 


The  edition  of  the  writer's  "  Insects  Injurious  to  Staple  Crops/' 
first  published  ten  years  ago,  having  been  exhausted,  the  pub- 
lishers requested  a  revision.  It  was  found,  however,  that  the 
advances  in  economic  entomology  during  the  past  decade  were  such 
that  it  was  necessary  to  practically  rewrite  the  book.  At  the 
time  it  was  first  published  two  other  books  were  projected;  one 
to  deal  mth  the  insects  affecting  garden  crops,  and  the  other  to 
discuss  those  affecting  fruits.  Pressure  of  regular  work  pre- 
vented the  author  from  completing  the  manuscript  for  these 
works  and  in  1907  Dr.  Chittenden  issued  his  excellent  book  on 
"  Insects  Injurious  to  Vegetables,"  so  that  there  seemed  to  be 
no  immediate  demand  for  another  volume  on  that  subject.  At 
the  same  time  two  other  well-known  entomologists  were  work- 
ing upon  books  which  would  cover  fruit  insects,  so  that  the 
writer  abandoned  the  field  to  them.  Subsequently,  the  work 
of  one  of  these  friends  was  cut  short  by  his  sudden  death,  and 
the  other  abandoned  the  task,  at  least  for  the  present. 

Under  these  circumstances,  it  seemed  that  there  was  a  distinct 
place  for  a  book  to  cover  all  the  insects  affecting  the  crops  of 
farm,  garden  and  orchard,  and  having  leisure  to  devote  to  it,  the 
author  developed  the  work  in  its  present  form. 

It  has  been  the  author's  effort  to  discuss  all  of  the  more  impor- 
tant insects  of  farm,  garden  and  orchard  at  sufficient  length 
to  give  a  clear  idea  of  their  life  histories  and  habits,  and  also  the 
best  means  of  control,  so  that  the  book  may  be  used  as  a  reference 
work  both  by  the  student  of  economic  entomology  and  by 
the  practical  farmer,  gardener,  or  fruit-grower.     Insects  of  minor 


VI  PREFACE 

or  local  importance  have  been  purposely  omitted.  The  insects 
of  practically  all  of  the  leading  crops  are  considered,  except  the 
citrous  fruits.  With  these  the  author  is  unfamiliar,  but  it  is 
hoped  to  add  a  chapter  upon  them  by  a  competent  authority 
in  a  subsequent  edition.  In  general,  the  discussion  of  insects 
and  their  control  as  given  is  based  upon  conditions  east  of  the 
Rockies,  and  practically  no  consideration  has  been  given  to  the 
conditions  of  the  Pacific  Coast  or  of  the  irrigated  country  of  the 
far  West. 

The  author  is  well  aware  that  there  are  doubtless  many  errors 
of  fact  or  of  wrong  emphasis  in  these  pages.  Such  must  nec- 
essarily be  the  case  in  a  work  the  greater  part  of  which  must  be 
compiled.  All  of  the  leading  authorities  on  the  subjects  discussed 
have  been  consulted  and  the  writer  has  endeavored  to  present 
their  evidence  fairly,  with  such  interpretation  as  his  personal 
knowledge  made  possible.  He  will  be  greatly  indebted  to  those 
who  will  aid  him  in  securing  the  accuracy  of  the  work  by  report- 
ing any  errors  or  by  suggesting  improvements  in  it,  as  it  is  hoped 
to  revise  the  pages  from  time  to  time  so  that  they  may  serve 
as  a  reliable  reference  work  upon  our  insect  pests  of  the  farm, 
the  garden,  and  the  orchard. 

On  the  following  pages  are  given  the  sources  from  which 
the  illustrations  have  been  secured,  but  the  author  wishes  to 
express  his  special  appreciation  of  the  very  large  number  of  figures 
which  were  furnished  him  by  Dr.  L.  0.  Howard,  Chief  of  the 
Bureau  of  Entomology,  and  Mr.  J.  A.  Arnold,  Chief  of  the 
Division  of  Publications,  of  the  United  States  Department  of 
Agriculture,  either  as  electrotypes  or  original  drawings  or  photo- 
graphs, and  to  Ginn  &  Company  of  Boston  for  the  loan  of 
numerous  electrotypes  made  for  an  Elementary  Entomology  by 
Prof.  C.  F.  Jackson  and  the  writer,  now  being  published  by 
them. 

E.  DwiGHT  Sanderson. 
West  Virginia  University, 
morgantown, 


SOURCES  OF  ILLUSTRATIONS 


The  author  wishes  to  express  his  very  sincere  appreciation 
of  the  courtesy  extended  him  by  those  friends  mentioned  below 
who  have  furnished  or  loaned  him  electrotypes,  photographs  or 
drawings,  thus  making  possible  the  anii)Ie  illustration  of  this 
volume. 

From  the  United  States  Department  of  Agriculture,  through 
the  courtes}^  of  Dr.  L.  O.  Howard,  Chief  of  the  Bureau  of 
Entomology  and  of  Mr.  J.  A.  Arnold,  Chief  of  the  Division 
of  publications,  the  following  illustrations  were  secured,  either 
as  electrotypes  or  as  new  plates  made  from  the  original  drawings 
or  photographs:  Figs.  1,  2,  3,  4,  24,  50,  53,  55,  59,  61,  66,  83, 
85,  86,  88,  90,  91,  93,  94,  95,  96,  101,  102,  103,  104,  105,  106, 
110,  113,  114,  117,  124,  125,  126,  127,,  128,  129,  130,  131,  132, 
133,  136,  137,  138,  139,  140,  141,  142,  143,  144,  145,  146,  148,  149, 
150,  153,  154,  158,  159,  160,  161,  162,  163,  164,  167,  168,  170, 
171,  172,  173,  174,  175,  176,  180,  181,  182,  183,  184,  185,  186, 
187,  188,  189,  192,  198,  199,  200,  201,  202,  203,  204,  205,  206, 
207,  208,  211,  216,  218,  221,  222,  223,  224,  225,  226,  227,  228, 
230,  231,  232,  235,  236,  240,  241,  242,  244,  246,  247,  248,  257,  258, 
262,  264,  265,  266,  270,  271,  272,  273,  274,  277,  281,  283,  285, 
292,  293,  294,  295,  296,  297,  298,  300,  304,  306,  307,  325,  326, 
353,  354,  355,  356,  377,  379,  394,  395,  396,  398,  400,  401,  402, 
404,  406,  413,  431,  432,  438,  446,  449,  472,  474,  475,  480,  487, 
490,  496,  497,  502,  503,  504,  505,  508,  and  512. 

The  following  illustrations  were  originally  prepared  by  Dr. 
C.  V.  Riley  and  have  been  secured  from  various  sources:  Figs. 
5,  7,  8,  9,  10,  12,  54,  60,  62,  63,  64,  65,  67,  68,  69,  74,  75,  76,  77, 

vij 


viii  SOURCES  OF  ILLUSTRATIONS 

78,  79,  80,  98,  99,  107,  147,  152,  212,  213,  214,  215,  220,  243, 
259,  260,  261,  320,  473. 

Dr.  S.  A.  Forbes,  State  Entomologist  of  Illinois,  Urbana,  111., 
kindly  furnished  the  following:  Figs.  50,  51,  56,  58,  120,  121,  122, 
123,  151,  156,  157,  234,  299. 

Prof.  G.  W.  Herrick  of  the  Cornell  University  Agricultural 
Experiment  Station  furnished  electrotypes  and  photographs  of 
the  following  illustrations  by  Dr.  Slingerland:  Figs.  57,  84,  87, 
249,  250,  251,  253,  254,  338,  344,  345,  346,  347,  348,  360,  361, 
362,  363,  364,  373,  381,  382,  383,  384,  422,  437,  482,  483,  485, 
486,  495,  498,  499,  500,  501,  513. 

Prof.  F.  L.  Washburn,  State  Entomologist  of  Minnesota, 
kindly  furnished  the  following  and  also  some  of  the  figures  of 
Dr.  Riley  listed  above:   81,  330,  343,  350,  351,  378,  380,  491. 

Prof.  H.  A.  Gossard  of  the  Ohio  Agricultural  Experiment 
Station  furnished  the  follo^ving:   89,  108,  341,  342. 

Prof.  R.  H.  Pettit,  Entomologist  of  the  Michigan  Agricultural 
Experiment  Station,  furnished  the  following:  92,  100,  245, 
and  341. 

Prof.  C.  P.  Gillette,  Director  of  the  Colorado  Agricultural 
Experiment  Station,  supplied  figures  229,  239,  352,  439,  450, 
506,  507,  and  511. 

Dr.  J.  B.  Smith,  Entomologist  of  the  New  Jersey  Agricultural 
Experiment  Station,  loaned  the  following  and  also  some  of  the 
Riley  figures:  13,  20,  109,  209,  210,  303,  308,  309,  323,  324, 
327,  334,  335,  336,  and  337. 

Prof.  P.  J.  Parrott  kindly  sent  photographs  of  the  following 
from  the  files  of  the  New  York  State  Agricultural  Experiment 
Station:  Figs.  340,  349,  399,  465,  466,  493,  494,  509,  510. 

Prof.  W.  E.  Rumsey  of  the  West  Virginia  Agricultural  Exper- 
iment Station  kindly  loaned  photographs  of  the  following:  357, 
358,  359,  367,  368,  369,  370,  385,  386,  387,  388,  389,  441,  444. 

Prof.  H.  Garman  of  the  Kentucky  Agricultural  Experiment 
Station  furnished  Figs.  97,  165,  166,  and  238. 

Director  R.  W.  Thatcher  of  the  Washington  Agricultural 
Experiment  Station  furnished  Figs.  237,  328,  329,  and  339. 


SOURCES  OF  ILLUSTRATIONS  IX 

Dr.  S.  J.  Hunter  of  the  University  of  Kansas  loaned  electro- 
types of  Figs.  112  and  113. 

Prof.  T.  B.  Symons  of  the  Maryland  Agricultural  Experiment 
Station  loaned  electrotypes  of  Figs.  119,  267,  310,  311,  312, 
313,  and  314. 

Prof..  H.  E.  Summers  of  the  Iowa  Agricultural  Experiment 
Station  loaned  drawings  of  Figs.  154,  and  333. 

Director  P.  H.  Rolfs  of  the  Florida  Agricultural  Experiment 
Station  loaned  photographs  of  Figs.  169  and  302. 

Director  T.  C.  Johnson  of  the  Virginia  Truck  Experiment 
Station  furnished  copy  for  Figs.  217  and  269. 

The  Orange  Judd  Company  of  New  York  City  kindly  furnished 
electrotypes  of  Figs.  219,  301  and  three  of  the  Riley  figures. 

Director  J.  C.  Kendall  of  the  New  Hampshire  Agricultural 
Experiment  Station  loaned  the  following  electrotypes  and  several 
of  the  author's  illustrations:  34,  43,  49,  118,  256,  322,  397,  417, 
445,  447  and  448. 

Director  S.  W.  Fletcher  of  the  Virginia  Agricultural  Exper- 
iment Station  and  Dr.  E.  A.  Back  of  the  Virginia  Crop  Pest 
Commission  furnished  the  following:  Figs.  36,  393,  440,  442, 
and  443. 

Dr.  W.  E.  Britton,  State  Entomologist  of  Connecticut,  fur- 
nished electrotypes  and  photographs  of  the  follo^ving:  Figs.  41, 
284,  305,  390,  416,  426,  429,  430,  477,  478,  479. 

Prof.  R.  I.  Smith  of  the  North  Carolina  Agricultural  Exper- 
iment Station  furnished  photographs  of  Figs.  280,  and  291. 

Prof.  A.  L.  Quaintance  furnished  photographs  of  Figs.  282, 
286,  287,  288,  289,  and  290. 

Director  F.  B.  Mumford  of  the  Missouri  Agricultural  Exper- 
iment Station  loaned  Figs.  434  and  435. 

Prof.  C.  S.  Crandall  of  the  Illinois  Agricultural  Experiment 
Station,  loaned  drawings  of  Figs.  436  and  492. 

Messrs.  Houghton,  Mifflin  &  Co.  furnished  Fig.  221,  from  the 
Riverside  Natural  History. 

The  Friend  Manufacturing  Company  contributed  Fig.  45. 

The  Deming  Company  furnished  Figs.  27,  28,  30,  33,  and  39. 


X  SOURCES  OF  ILLUSTRATIONS 

F.  E.  Myers  &  Bro.  furnished  Figs.  29  and  45. 

The  Spramotor  Company  supplied  Fig.  31. 

E.  C.  Brown  &  Co.  donated  Figs.  32  and  40. 

The  Goulds  Manufacturing  Company  supplied  Fig.  46. 

The  following  figures  are  original  or  are  the  author's  illus- 
trations: 6,  11,  14,  15,  16,  17,  18,  19,  23,  25,  37,  38,  42,  44,  46, 
47,  48,  52,  70,  71,  72,  73,  82,  111,  134,  135,  177,  178,  179,  190, 
191,  193,  194,  195,  196,  197,  233,  252,  255,  263,  268,  275,  276, 
278,  279,  315,  316,  317,  318,  319,  331,  332,  391,  392,  403,  405, 
407,  408,  409,  410,  411,  412,  414,  415,  418,  419,  420,  421,  433, 
451,  452,  453,  454,  455,  456,  457,  458,  459,  460,  461,  462,  463, 
464,  465,  467,  468,  469,  470,  471,  481,  483,  488,  and  489. 


CONTENTS 


Preface v 

Sources  oe  Illustrations  and  Ackno\vled(;ments vii 

CHAITER  PAGE 

I.  Injury  to  Crops  by  Insect  Pests 1 

II.  Beneficial  Insects,  Predaceous  and  Parasitic U 

III.  Structure  and  Development  of  Insects 22 

IV.  Farm  Methods  for  the  Control  op  Insects 32 

V.  Insecticides 42 

VI.  Spraying  and  Dusting  Apparatus 60 

VII.  Insects  Affecting    Grains,   Grasses,    Forage    and    Mis- 
cellaneous Crops 79 

VIII.  Insects  Injurious  to  Small  Grains .  121 

IX.  Insects  Injurious  to  Corn 157 

X.  Insects  Injurious  to  Stored  Grains 186 

XI.  Insects  Injurious  to  Clover 200 

XII.  Insects  Injurious  to  Tobacco 222 

XIII.  Insects  Injurious  to  Cotton 241 

XIV.  Insects  Injurious  to  the  Hop-plant 273 

XV.  Insects  Injuriolts  to  Potatoes  and  Tomatoes 285 

XVI.   InsECTS  Injurious  to  Beans  and  Peas 305 

XVII.  Insects  Injurious  to  Beets  and  Spinach 330 

XVIII.  Insects  Injuriolts  to  Cabbage  and  Cruciferous  Crops  .  .  .   347 

XIX.  Insects  Injurious  to  Melons,  Cucltmbers,  Squash,  etc.  .  .   379 

XX.  Insects  Injurious  to  Miscellaneous  Garden  Crops....   402 

XXI.  Insects  Injurious  to  the  Sweet  Potato 430 

XXII.  Insects  Injurious  to  the  Strawberry 441 

XXIII.  Insects  Injurious  TO  the  Raspberry  and  Blackb::rry.  . .  459 

XXIV.  Insects  Injurious  to  the  Currant  and  Gooseberry 477 

xi 


xii  •  CONTENTS 

CHAPTER  PAGE 

XXV.  Insects  Injurious  to  the  Grape 492 

XXVI.  Some  Insects  Injurious  to  Orchard  Fruits 538 

XXVII.  Insects  Injurious  to  the  Apple  and  Pear 582 

XXVIII.  Insects    Injurious    to    the    Peach,    Plum,    Cherry    ant) 

Stone  Fruits 645 

Index •  671 


INSECT  PESTS 

OP 

FARM,  GARDEN  AND  ORCHARD 


CHAPTER  I 

THE  INJURY  TO  CROPS  BY  INSECT  PESTS 

Ever  since  the  locust  plagues  in  the  time  of  the  Pharaohs  his- 
tory is  replete  with  accounts  of  insect  scourges  and  the  enormous 
losses  they  have  caused  the  agriculturists  of  all  ages.  However, 
instead  of  diminishing  with  the  advancement  of  agricultural 
methods,  injurious  insects  have  undoubtedly  become  both  more 
numerous  and  more  destructive  in  modern  times.  "  In  no  coun- 
trj'  in  the  world  do  insects  impose  a  heavier  tax  on  farm  products 
than  in  the  United  States.  The  losses  resulting  from  the  depre- 
dations of  insects  on  all  the  plant  products  of  the  soil,  l)oth  in 
their  growing  and  in  their  stored  state,  together  with  those  on 
live  stock,  exceed  the  entire  expenditures  of  the  National  Gov- 
ernment, including  the  pension  roll  and  the  maintenance  of  the 
Army  and  the  Navy."*  "  Very  careful  estimates,  based  on  crop 
reports  and  actual  insect  damage  over  a  series  of  years,  show 
that  the  loss  due  to  insect  pests  of  farm  products,  including 
fruits  and  live  stock,  now  reaches  the  almost  inconceivable  total 
of  $1,000,000,000,  annually. "t  The  above  quotations  from  Mr. 
C.    L.   Marlatt,  Assistant   Chief   of   the  Bureau   of   Entomology, 

*  C.  L.  Marlatt,  Yearbook  U.  S.  Department  of  Agriculture,  1904,  p.  461. 
t  C.  L.  Marlatt,  Journal  of  Economic  Entomology,  IV,  109. 


2  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

United  States  Departnient  of  Agriculture,  may  appear  to  the 
reader  either  kidicrous  or  startHng,  according  to  whether  he  be 
more  or  less  informed  concerning  the  important  role  which  insects 
play  in  our  agricultural  economy,  which  in  turn  forms  the  warp 
of  American  prosperity. 

A  brief  resume  of  the  records  of  damage  done  by  insect  pests, 
of  the  cost  of  fighting  them,  and  of  the  estimates  which  form  the 
basis  of  the  above  statement,  will  make  it  the  more  convinc- 
ing. 

Growing  Cereals. — Probably  no  other  insect  does  so  widespread 
damage  as  the  Hessian  fly,  attacking  our  chief  staple,  wheat,  as 
well  as  rye  and  barley.  One-tenth  of  the  whole  crop,  valued 
at  $50,000,000  to  $70,000,000,  is  generally  conceded  to  be  de- 
stroyed by  this  pest  every  year.  In  certain  sections  the  loss  often 
amounts  to  from  30  to  50  per  cent,  and  in  1900  was  estimated 
at  fully  $100,000,000  (Marlatt,  I.e.).  The  southern  grain  louse 
or  "  green  bug  "  caused  a  loss  estimated  at  from  $5,000,000  to 
$10,000,000  in  Texas,  Oklahoma  and  Kansas  in  1907,  and  every 
year  there  is  a  considerable  shrinkage  of  the  wheat  crop  due  to 
the  work  of  various  species  of  plant-lice  whose  injury  doubtless 
amounts  to  2  or  3  per-  cent  of  the  crop,  worth  $15,000,000  to 
$20,000,000. 

The  corn  crop  of  the  United  States  was  worth  $1,720,000,000 
in  1909.  One  of  the  worst  pests  of  this  crop  in  the  Mississip])i 
Valley  is  the  (diinch-ljug.  Several  years  ago  Professor  F.  M. 
Webster  estimated  the  'loss  from  this  insect  since  1850  at 
$330,000,000,  and  at  present  it  probably  destroys  at  least  2  per 
cent  of  the  corn  crop  every  year,  worth  over  $30,000,000,  and  in 
many  years  the  loss  is  much  more.  The  western  corn  root-worm 
and  the  corn  root-aphis  which  work  unnoticed  on  the  roots 
of  the  corn  throughout  the  same  territory  cause  an  equal  loss. 
The  corn  ear-worm  often  destroys  from  5  to  10  pei-  cent  of  the 
crop  in  the  South,  and  throughout  the  Corn  I^qM  it  undoubtedly 
decreases  the  crop  by  2  or  3  per  cent. 

The  total  value  of  cereal  crops  in  the  United  States  in  1909 
was  practically  $3,000,000,000,  which  was  undoubtedly  decreased 


THE  INJURY  TO  CROPS  BY  INSECT  PESTS  3 

by  10  per  cent  due  to  the  ravages  of  insect  pests,  which  thus 
taxed  our  grain  growers  some  $300,000,000. 

Hay  and  Forage  Crops. — A  host  of  small  insects  attack  our 
grasses  and  forage  crops,  many  of  them  being  so  small  that  they 
are  unnoticed,  though  their  aggregate  injury  is  something  enormous. 
Of  the  larger  pests  of  grasses  and  forage  plants  the  army  worms 
are  among  the  best  known  and  have  often  caused  a  loss  of  over 
half  a  million  dollars  to  a  single  State  in  one  season.  Grass- 
hoppers of  various  species  are  also  always  more  or  less  injurious 
and  often  become  a  serious  menace.  Probably  the  most  serious 
injury,  however,  is  done  by  subterranean  larvie  such  as  the  cut- 
worms, wireworms,  white  grubs,  and  webworms,  which  breed  in 
sod  land,  and  by  the  hordes  of  little  leaf-hoppers  which  are 
always  prevalent,  but  whose  injury  often  passes  unnoticed.  Ten 
per  cent  of  the  hay  crop  was  worth  $65,000,000  in  1909,  and  this 
is  a  fair  estimate  of  the  damage  done  to  ha}'  and  forage  crops 
by  their  insect  enemies. 

Cotton. — The  cotton  plant  has  a  number  of  injurious  insect 
enemies,  of  which  the  boll  weevil,  bollworm,  and  leafworm  are 
the  most  injurious.  In  1904  the  writer  made  a  statistical  study 
of  the  decrease  in  the  cotton  crop  of  Texas  due  to  the  boll 
weevil,  and  showed  that  it  was  then  costing  that  State  $25,000,000 
per  annum.*  This  estimate  has  been  confii-med  by  independent 
investigations  made  by  Mr.  W.  D.  Hunter  of  the  U.  S.  Bureau 
of  Entomology,  and  although  the  loss  in  Texas  is  not  so  serious 
at  present,  the  weevil  has  spread  eastward  into  Alabama,  so 
that  its  total  injury  remains  practically  the  same,  and  has 
undoubtedly  l:)een  a  large  factor  in  the  higher  price  of  cotton 
in  recent  years.  The  bollworm  is  most  injurious  in  the  south- 
western cotton-producing  States,  where  it  causes  a  loss  of  from 
5  to  60  per  cent  of  the  crop.  The  total  damage  to  cotton  by 
the  l^ollworm  is  approximateh^  $20,000,000  per  annum  and  not 
infreciucntly  exceeds  that  amount.     In   ISSO  the  United  States 

*  E.  D.  Sanderson,  The  Boll  Weevil  and  the  Cotton  Crop  of  Texas.  (Bul- 
letin Dept.  of  Agriculture,  Insurance,  Statistics  and  History,  Austin,  Texas, 
1905,  p.  28,  7  maps.) 


i  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Entomological  Commission  made  an  investigation  of  the  cotton 
worm  and  valued  its  ravages  at  S30,000,000,  but  with  the 
extensive  use  of  Paris  green  and  arsenical  poisons  its  injury  has 
been  greatly  reduced  and  now  amounts  to  from  $5,000,000  to 
$10,000,000  annually.  Various  minor  pests  of  the  cotton  plant 
inflict  a  considerable  amount  of  local  injury  and  with  the  above 
pests  damage  the  crop  at  least  10  per  cent,  worth  $85,000,000 
in  1909. 

Tobacco. — Tobacco  is  attacked  by  insects,  which  form  one 
of  the  chief  "  bugbears  "  of  tobacco  growing,  at  all  stages  of  its 
existence.  Ten  per  cent  of  the  crop,  worth  $10,000,000,  is  cer- 
tainly destroyed  by  them  every  j^ear. 

Truck  Crops. — Truck  crops  are  peculiarly  susceptible  to 
insect  attacks,  and  their  control  forms  one  of  the  chief  items  in 
the  cost  of  production.  It  is  safe  to  say  that  truck  crops  suffer 
from  insect  ravages  full}^  twice  as  much  as  do  the  staples,  or  20 
per  cent  of  their  total  value.  Statistics  are  not  available  for 
the  present  value  of  truck  crops,  but  they  were  probably  worth 
$300,000,000  in  1909,  making  the  insect  tax  for  the  trucker 
fully  $60,000,000. 

Fruits. — Fruit  trees  are  also  much  more  seriously  injured 
by  insects  than  are  the  staple  crops,  and  their  control  involves 
a  large  expense  to  the  fruit-grower.  Where  it  is  not  combated, 
the  codling  moth,  or  apple  worm,  would  cause  a  loss  of  from 
30  to  50  per  cent  of  the  crop,  and  where  it  is  controlled  by 
spraying  a  consideral)le  expense  is  involved.  The  loss  and  cost 
of  treatment  for  this  pest  alone  amount  to  $20,000,000  for  the 
United  States,  and  were  it  not  for  the  fact  that  it  is  now  largely 
controlled  in  the  principal  fruit-growing  sections,  the  loss  would 
be  double  or  treble  this  sum.  The  loss  due  to  the  San  Jose  scale 
is  difficult  to  estimate,  but  it  is  well  known  that  it  has  destroyed 
millions  of  trees  and  that  in  the  principal  fruit  regions  where  this 
pest  is  prevalent  it  is  necessary  to  treat  the  trees  annually 
at  a  cost  of  from  10  to  25  cents  per  tree,  so  that  $10,000,000  a 
year  would  be  a  very  conservative  estimate  of  its  annual  cost. 
Both  deciduous  and  citrous  fruits  have  a  host  of  insect  pests, 


THE  INJURY  TO  CROPS   BY   INSECT  PESTS  5 

always  present  and  doing  more  or  less  damage  and  occasionall}' 
becoming  so  abundant  as  to  threaten  the  life  of  the  trees  or  their 
crops.  Twenty  per  cent  of  the  value  of  our  fruit  products, 
worth  at  least  $30,000,000,  is  certainly  destroyed  by  insect 
pests  every  year. 

Forest  Insects. — Only  those  who  have  had  opportunity  to 
observe  the  ravages  of  insects  in  timber  and  in  timber  products 
can  appreciate  the  enormous  losses  which  they  occasion.  Prob- 
ably no  one  is  better  informed  upon  this  matter  than  Dr.  A.  D. 
Hopkins,  in  charge  of  the  Forest  Insect  Investigations  of  the 
I'.  S.  Bureau  of  Entomolog}',  who  has  made  a  life  study  of  these 
pests  in  all  parts  of  the  country.  In  a  recent  circular  he  states  * 
that  "  the  amount  of  insect-killed  and  damaged  timber  left  in  the 
woods,  plus  the  reduction  in  value  of  that  utilized,  to  be  charged 
to  insects  is  not  far  from  an  equivalent  of  10  per  cent  of  the  value 
of  the  annual  output  of  forest  products  of  all  kinds,  in  the  rough. 
The  total  value  of  the  forest  products  of  the  United  States  in  1907 
is  given  as  $1,280,000,000;  the  losses  from  insect  depredations 
would  therefore  represent  an  annual  loss  in  cash  value  of  more 
than  $100,000,000."  To  this  should  be  added  a  similar  loss  to 
farm  woodlots,  which  may  be  estimated  at  an  additional  $10,000,- 
000.  The  insect  injury  to  the  shade  trees  of  city  streets,  parks, 
and  estates  should  also  be  mentioned,  for  such  pests  as  the  gypsy 
moth,  the  elm  leaf-beetle,  tussock  moths,  etc.,  are  not  only  causing 
enormous  losses  and  large  expense  for  their  control,  but  they  are 
often  destroying  the  values  of  real  estate  and  through  killing  the 
trees  are  destroying  the  scenic  value  of  property  and  changing  the 
esthetic  environment  in  a  manner  which  it  will  require  many 
decades  to  remedy,  if  the  previous  conditions  can  ever  be  even 
partially  reproduced.  The  State  Forester  of  Massachusetts  has 
recently  shown  that  the  New  England  States  and  the  Federal 
Government  have  spent  fully  $7,000,000  in  fighting  the  gypsy  and 
brown-tail  moths  in  New  England,  and  at  the  present  time  the 
New  England  States,  the  Federal  Government,  municipalities  and 
private  individuals  are  spending  fully  $1,000,000  per  annum 
*  A.  D.  Hopkins,  Circular  129,  Bureau  of  Entomology,  U.  S.  Dept.  Agr, 


6  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  this  warfare  for  the  preservation  of  their  shade  and  forest 
trees. 

Live  Stock. — Insect  pests,  incUiding  the  ticks  and  mites,  are 
almost  as  important  as  enemies  of  live  stock  as  of  crops.  The 
principal  drawback  to  cattle  raising  in  the  South  is  the  Texas 
fever,  transmitted  by  the  cattle  tick,  which  has  been  charged  by 
the  officials  of  the  Bureau  of  Animal  Industry  with  a  loss  of  SlOO,- 
000,000  annually.  The  ox-warble,  which  causes  the  "grubby" 
hides  of  cattle,  causes  a  loss  estimated  at  from  S10,000,000  to 
$35,000,000  per  year  due  to  the  depreciated  value  of  the  hitlos  and 
the  lessened  quantity  and  poorer  quality  of  the  beef  of  affected 
animals.  The  screw-worm  fly  is  a  constant  annoyance  to  cattle  and 
source  of  loss  on  the  range,  and  numerous  biting  and  parasitic  flies 
cause  a  considerable  loss  to  the  grower  of  live  stock,  both  through 
actual  damage  and  through  the  annoyance  preventing  growth  and 
production.  The  sheep  scab,  sheep  tick,  the  sheep  bot — causing 
''staggers"  or  "grub-in-the-head" — horn-fly,  buffalo-fly,  black-fly, 
and  numerous  species  of  lice  which  affect  all  of  the  domestic  ani- 
mals, are  among  the  pests  which  must  be  combated  by  the  stock- 
man. In  1909  the  live  stock  products  were  worth  $3,000,000,000, 
and  it  is  estimated  that  fully  10  per  cent  of  this  amount  was  lost 
through  injury  from  insects. 

Stored  Products. — Even  after  the  crops  have  been  gathered 
and  garnered,  and  indeed  after  they  and  animal  products  have 
been  manufactured,  they  are  constantly  subject  to  the  attacks  of 
numerous  "weevils,"  "moths,"  and  other  insect  pests  of  stored 
products.  Every  housewife  and  every  merchant  knows  that  only 
through  constant  surveillance  can  they  prevent  these  ravages. 
Mills,  tobacco  warehouses,  storage  houses,  and  vessels,  must  be 
frequently  cleaned  and  often  must  be  fumigated  to  prevent  the 
increase  of  insect  pests  peculiar  to  them.  It  is  estimated  that  at 
least  5  per  cent  of  the  cereal  crops  are  destroyed  by  insects  while 
in  storage,  which  would  mean  a  loss  of  $150,000,000,  and  in  many 
cases  the  loss  to  corn,  particularly  in  the  South,  is  much  greater. 
The  total  loss  due  to  insects  in  stored  goods  of  all  kinds  is  impos- 
sible to  estimate,  but  would  fall  not  far  short  of  $200,000,000. 


THE  INJURY  TO  CROPS   BY  INSECT   PESTS 


With  this  brief  survey  of  the  losses  thie  to  iiis(>ct  pests,  we  may 
summarize  them  in  a  table  which  will  show  that  the  total  is  based 
upon  conservative  estimates. 

Annual    Values  of    Farm    Products   and    Losses    Chargeable 
TO    Insect   Pests  * 


Product. 

Values. 

Percentage   of 
I-oss. 

Amount  of  Loss. 

Cereals 

$3,000,000,000 
665,000,000 
850,000,000 
100,000,000 

t  300,000,000 
95,000,000 

t  150,000,000 
110,000,000 

t  100,000,000 

3,000,000,000 

10 
10 
10 
10 
20 
10 
20 
10 
10 
10 

$300,000,000 
66,500,000 
85,000,000 
10,000,003 
150,000,000 
9,500,000 
30  000  000 

Hay  and  forage  . .       

Cotton                

Tobacco 

Truck  crops 

Sugars 

Fruits 

Farm  forests         

1 1  000  000 

Miscellaneous  crops 

10  000  000 

Animal  products 

300,000,000 

Total 

Natural     forests    and    forest 
products 

$8,370,000,000 

$972,000,000 

100,000,000 
200  000  000 

Products  in  storage 

Grand  total 

$1  272  000  000 

*  Basccl    upon    table   of  C.    L     Marlatt,    I.e.,  niodifi;'d    by   stati.stio.s  of  the   Secretary  of 
Agriculture,  Yearbook  V .  S.  Department  of  Af;riiultnre  for  1909. 
t  E.5timated. 

One  l)illion  dollars  is  thus  a  conservative  estimate  of  the 
damage  done  to  staple  crops,  fruits,  truck  crops,  domestic  animals, 
timber  and  stored  products  by  these  apparently  insignificant 
insects. 

Yet  there  is  another  aspect  to  the  matter.  "  One  man's  loss 
is  another  man's  gain"  is  never  more  true  than  as  regards  these 
losses  occasioned  by  insects;  for,  through  widespread  injury  by 
them,  prices  rise,  while  if  these  injuries  did  not  occur  and  corre- 
spondingly large  crops  were  placed  upon  the  market,  prices  must 
surely  fall.  These  estimates  of  losses  due  to  insects  are  then  very 
largely  comparative.  Yet,  to  a  large  extent,  they  are  still  real 
losses,  the  same  as  are  those  occasioned  by  fire  and  storm;    for 


8  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

though  a  .siuall  crop  iiuiy  l)iing  better  prices,  it  is  usually  at  the 
expense  of  individuals  or  communities  which  have  sustained  ex- 
ceptionally heavy  losses.  Were  these  losses  evenly  distributed 
among  all  those  producing  a  given  crop,  there  would  be  no  real 
hardship  to  them;   but  such  is  by  no  means  the  case. 

All  this,  then,  goes  to  emphasize  the  fact  that  the  successful 
farmer — as  the  successful  man  in  any  other  trade  or  profession — 
is  the  one  who  is  able  to  overcome  obstacles  which,  though  pos- 
sibly ruining  his  neighbor,  are  making  a  good  market  for  his  special 
crop;  for  these  insect  pests  can  be  largely  overcome.  The  millen- 
nium will  doubtless  come  before  the  farmer  will  be  able  to  stop 
fighting  them,  but  a  large  part  of  the  damage  by  them  can  be  pre- 
vented at  a  cost  which  renders  it  profitable.  Rational  methods  of 
general  farm  practice  with  the  proper  use  of  apparatus  and  insecti- 
cides, even  such  as  are  now  known,  and  in  which  improvements 
are  being  constantly  made,  if  intelligently  used  l)y  American 
farmers,  would  save  to  them  the  larger  part  of  this  enormous  loss. 


CHAPTER  II 
BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC 

Ladybird-beetles 

After  liLs  tstra\vbc'ni(\s  have  been  luincd  by  the  stiawbeny 
weevil,  the  garden  truck  l)y  eutworms,  the  wheat  despoiled  by  the 
Hessian  fly,  the  melon-patch  fallen  a  pre}'  to  plant-lice,  and  the 
fruit  crop  has  been  a  failure  on  account  of  the  codling  moth,  plum 
curculio,  and  San  Jose  scale,  it  is  scarcely  surprising  that  the 
farmer  does  as  one  of  my  acquaintances  did  and  "orders  the  hands 
to  kill  everything  that  craw^ls." 

But  such  would  be  entirely  too  heroic  a  measure,  and  if  strictly 
adhered  to  the  remedy  would  be  as  bad  as  the  disease,  for  it  would 
mean  not  only  useless  labor,  but  the  destruction  of  the  most  effect- 
ive means  whereby  insect  pests  are  held  in  check.  We  pride 
ourselves — and  justly — that  with  our  spray  pumps  and  deadly 
sprays  many  crops  can  be  effectually  protected;  but  were  it  not 
for  those  other  insects  which  feed  upon  these  injurious  forms, 
what  an  enormous,  and,  in  some  instances,  almost  futile  task  it 
would  be ! 

Among  these  beneficial  insects  the  little  ladj'bird-beetles  of 
the  family  Coccinellidce  are  entitled  to  be  in  the  first  rank. 
Almost  all  the  beetles  and  larvae  feed  upon  plant-lice  and  scale 
insects.  Of  such  value  are  those  feeding  upon  scale  insects 
that  not  many  years  ago  several  Australian  species  were 
imported  into  California  that  they  might  prey  upon  the  San 
Jose  and  other  scales.  One  of  these  was  eminently  successful 
and  almost  completely  destroyed  the  cottony  cushion-scale. 

Of  those  feeding  upon  plant-lice,  one  of  the  most  common 
is    the    Nine-spotted    Ladybird    (Coccinella    novemnotata).     This 

9 


10        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

beetle  is  about  one-fourth  of  an  inch  long,  with  black  head  and 
body.  The  wing-covers  are  orange-yellow  marked  with  nine 
black  spots — four  on  each  side  and  one  on  the  central  suture. 
The  larva  has  been  fancied  to  resemble  a  miniature  alligator; 
it  is  nearly  twice  as  long  as  wide,  almost  black,  marked  with 
bluish  and  orange  spots,  and  has  long  legs,  which  carry  it  around 
quite  rapidly.  The  beetles  hibernate  during  the  winter  and 
come  forth  in  the  spring  and  lay  their  eggs  wherever  the  young 
will  be  able  to  find  food  when  they  hatch.  When  the  larva 
has  satisfied  its  ravenous  appetite  and  become  full  grown  it 
fastens  itself  to  a  leaf  or  twig, — sceminglv  Ijv  its  tail,   if  such 


Fig.    1. — The     nine-spotted    ladybird     {CoccineWi     novcnmotatu),     and     its 
larva  enlarged.     (After  Chittenden,  IT.  S.  Dept.  Agr.) 

a  term  might  be  allowed, — transforms  to  the  pupa,  and  in  a  week 
or  ten  days  the  adult  beetle  emerges  from  the  pupal  skin.  This 
life-cycle  is  repeated  several  times  during  the  summer  season, 
before  the  fall  brood  enters  winter  quarters. 

Another  very  common  form  among  plant-lice  on  garden  truck 
is  the  little  Adalia  bipunctata,  or  Two-spotted  Ladybird.  It  is 
slightly  smaller  than  the  preceding,  and  with  only  one  black  spot 
on  each  wing-cover  (Fig.  2) . 

Several  other  species  in  the  genus  Hippodamia  are  very 
useful,  and  among  them  the  Convergent  Ladybird  (Hippo- 
damia  convergens)  is  one  of  the  Ijcst  known.  Its  name  is  received 
from  two  white  dashes  on  the  ])lack  thorax,  which  converge 
posteriorly.     The  thorax  lias  also  a  white  nuirgin,  and  there  are 


BENEFICIAL  INSECTS,   PREDACEOUS   AND  PARASITIC      11 

thirteen  black  clots  on  its  orange  wing-covers.  These  larvae 
and  beetles  are  very  common  among  the  plant-lice  on  melon- 
vines,  and  are  an  important  factor  in  their  extermination.     They 


-ym-. 


Fig.  2. — The  two-spotted  hu\y\nrd  {Adalia  bipunctata):  «,  l;irv;i;  6,- mouth- 
parts  of  same;  c,  claw  of  same;  d,  pupa;  e,  advilt;  /,  antenna  of  same; 
all  enlarged.     (After  Marlatt,  U.  S.  Dept.  Agr.) 


Fig.  3. — The  convergent  ladybird  {Hippodamia  convergenfi) :  n,  adult;  h,  pupa; 
c,  larva;  enlargeil.      (After  Chittenden,  U.  S.  Dept.  Agr.) 


have  also  been  noted  for  eating  the  black  peach  aphis  and  many 
other  plant-lice. 

A  form  which  is  often  very  al)undant  among  plant-lice  on  corn 
is  the  Spotted  Ladybird  {Megilla  maculdta).  The  head,  thorax, 
and  wing-covers  are  a  dai'k  pink,  with  two  black  spots  on  the 


12        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

thorax  and  ten  on  the  wing-covers.  Such  nuniljcrs  of  these 
little  fellows  have  frequently  been  found  huddled  together  under 
the  rubbish  at  the  base  of  some  tree  in  a  last  year's  cornfield 
that  they  might  be  taken  up  by  the  handful  without  difficulty. 


Fig.  4. — The  spotted  ladybird  {Megilla  maculata):  a,  larva;  6.  pupa;.c,  adult; 
enlarged.      (After  C'.ittenden,  U.  S.  Dept.  Agr.) 


Many  other  species  feed  upon  plant-lice,  but  the  al:)Ove  are  the 
most  common,  and  all  bear  a  resemblance  to  one  another,  being 
generalh'  orange  or  red  with  black  spots,  and  of  a  characteristic 

round  or  oval  form,  flattened  below. 

so  that  the  legs  may  be  drawn  in 

luidcr  the  wing-covers. 

Those  ladybirds  which  feed  upon 

scales   are   much    smaller    and    are 


Fig.    5. -The     twice-stabbed     ^^1'^^"^'   though    sometimes    spotted 
ladybird    {Chilocorus  bivulnc-      with  red  or  orange. 

?w.s).    a,  adult;  b,  larva;   en-  v       r  i  j.i    ,.      • 

,1      T^c.     r.-i     N  As   far    as   known,    there   is   no 

larged.     (After  Riley.)  _  ' 

wav    in    which    these    useful    allies 


may  be  encouraged  or  increased  in  luimbers,  but  it  is  trusted 
that  the  above  ma}^  give  such  a  brief  view  of  their  habits  that 
fewer  may  be  killed  through  ignorance  concerning  their  true 
worth, 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC     13 

Syrphus-flies 

Besides  the  little  beetles  described  al)0\'e  there  is  a  family 
of  flies,  the  Syrphidoe,  many  of  whose  larva-  feed  upon  plant- 
lice.  This  family  is  a  very  large  on(\  and  thus  the  habits  of  its 
tlifferent  members  vary  considerably.  One  of  them,  the  drone- 
fly,  so  closel}'  reseml^les  a  hone}'- 
bee  as  to  be  almost  indistin- 
guishable from  it.  The  larva  of 
this  fly  (Eristalis  tenax)  is  one 
of  the  common  rat-tailed  mag- 
gots which  are  found  in  putrid 
matter.     It  is  thought  .that  the 

old    "  bugonia "    superstition    of      ^^^^  ^      c      ;.,     •;     ■■        i        i 
<=  ^  riG.  6. — j>iyrp/nis  ribefiit ;  enlarged. 

the  ancients  that  bees  came  from 

maggots  in  dead  aninmals,  etc.,  was  due  to  the  confusion  of  this 

fly  with  honey-bee. 

In  another  group  of  the  family,  the  adult  flies  of  which  also 
quite  closely  resemble  bees,  the  larvas  are  parasitic  in  the  nests 
of  honey-  and  bumble-bees,  feeding  upon  their  larVcC. 

But  the  larvse  of  possibly  the  most  typical  portion  of  the 
family,  embracing  the  genus  Syrphus  and  its  near  allies,  are 
entirely  predaceous  upon  plant-lice.  Rarely  can  a  colony  of 
plant-lice  be  found  without  some  of  these  little  enemies  hard 
after  them. 

The  adult  syi'phus-fly  is  a  very  sti'iking  insect,  \\\\h  its  dark 
green  metallic  thorax,  and  abdomen  variously  banded  with 
yellow  and  black.  The  female  fly  lays  her  eggs  upon  some  plant 
bearing  plant-lice.  The  larvse  which  hatch  from  tliese  are  elongate, 
flattened  maggots,  about  one-half  an  inch  long,  with  hardly  a 
trace  of  a  head,  but  with  four  small  hooks,  which  serve  as  jaws, 
projecting  from  the  more  pointed  end  of  the  body.  These  mag- 
gots are  often  of  a  light-green  color,  and  so  like  the  color  of 
the  plants  as  to  render  them  most  difficult  to  recognize.  The 
young  larvffi  at  once  commence  crawling  over  the  plant  in  search 
of    aphids,   and   as   soon   as  they  come  in  contact  with   one   it 


li        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

is  firnil}'  chispcd  l)y  the  small  liooklets  until  the  juices  are  sucked 
from  its  l:)0(ly.  In  this  manner  \'ery  large  numbers  are  destroyed, 
a  single  maggot  of  the  American  Syrphus-fiy  {Syrphus  americanus) 
having  been  observed  to  eat  twenty-five  apple  plant-lice  {Aphis 
pomi)  in  as  many  minutes.  When  the  larva  is  ready  to  pupate 
it  attaches  itself  to  a  leaf,  and  the  larval  skin  dries  up  and  forms 
a  case  or  puparium  inside  of  which  the  pupa  remains  until  it 
transforms  to  the  adult   fly. 

Though  most  of  these  larvaj  feed  upon  plant-lice  upon  the 
leaves,  one  of  them,  the  Root-louse  Syrphus-fly  {Pipiza  radiccms), 
lives  entirely  underground   during  that  stage,    and  feeds  upon 


Fig.    7. — The    root-louse   syrphus-fly     {Pipiza    radicans).      a,    maggot;     b, 
puparium;  r,  fly.      (After  Riley.) 

the  root-lice  of  the  apple  and  the  grape.  None  of  this  family 
are  injurious,  uiid  as  a  larg(>  portion  of  them  ai'e  so  ben(>ficial 
as  to  frequently  destroy  whol(>  bioods  of  ])laiit-lire,  they  should 
not  be  (listurl)ed  in  their  good  Moik  if  ])ossible  to  avoid  il. 

The  Ground-beetles 

If,  as  you  scrape  away  the  loose  chips  at  the  base  of  a  tree 
in  your  door-yard,  turn  over  an  old  log  in  the  woodland,  or  pick 
up  a  fallen  fence-rail,  you  will  scrutinize  the  inhabitants  under 
these  shelters,  a  number  of  shining  black  beetles  varying  in  length 
from  one-fourth  to  1  h  inches  will  usually  be  noticed.  If  the  city 
reader  be  not  so  fortunate  as  to  be  familiar  with  or  have  access 
to  these  hiding-places,  he  may  find  large  numbers  of  the  beetles 
under  any  electric  arc  light  during  the  warm  summer  evenings; 
for  there  they  are  having  a  sumptuous  banquet  upon  the  small 


BENEFICIAL  INSECTS,  PREDACEOUS  AND  PARASITIC     15 

flies  and  moths  attracted  by  the  glare.  The}'  are  rarely  seen 
at  large  during  the  day,  as  they  are  almost  exclusively  nocturnal 
insects,  and  from  their  habit  of  remaining  almost  entirely  in  or 
on  the  ground  they  are  usually  known  as  "  Ground-beetles."  As 
might  therefore  be  inferred,  they  are  exceedingly  valuable  to  the 
farmer  by  destroying  large  numbers  of  noxious  insects  which 
pass  a  part  or  all  of  their  existence  in  the  soil.  Besides  the 
glossy  black  forms  which  are  most  commonly  seen,  many  are 
brillianth'  marked  with  gold,  green,  purple,  and  iridescent  tints. 
The   Fiery   Ground-beetle    {Calonoma  calidum),   so   called   on 


Fig.   S. — The  fiery  ground-beetle    {Cidoaoina  culidum).     a,  beetle;    b,  larva; 
c,  "  the  searcher  "  (Calosoma  scrutator).     (After  Riley.) 


account  of  the  wing-covers  being  dotted  with  bright  gold,  has 
many  times  been  of  great  assistance  in  helping  to  rid  a  corn-field 
of  cutworms.  The  larvae  of  this  insect  are  about  one  inch  in 
length,  of  a  dark  brown  color,  with  the  skin  of  a  hard,  horny 
texture  like  that  of  the  beetle.  They  have  strong,  prominent 
jaws,  and  at  the  posterior  end  of  the  body  is  a  forked  appendage 
looking  much  like  another  pair  of  jaws.  It  is  not  only  surpris- 
ing that  these  larva  will  eat  so  large  a  number  of  cutworms, 
as  they  have  frequently  been  known  to  do,  but  that  they  will 
dare  to  attack  such  a  formidaljle  creature  fully  three  or  four 
times  as  large  as  themselves,  but  their  assault  is  sharp  and 
vigorous,  and  a  single  larva  has  often  been  seen  to  kill  and  eat 


10        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


several  full-grown  cutworms  in  a  short  time.  Many  instances 
of  the  good  work  of  this  beetle  are  on  record,  among  which  one 
by  the  late  Professor  J.  A.  Lintncr  may  be  cited,  where  he  found 
them  eating  large  numbers  of  the  corn-cfambus — sometimes 
locally  known  as  the  corn  bud-worm.  Another  somewhat  larger 
beetle,  called  by  Professor  J.  H.  Comstock  ''  the  Searcher  "  {Calo- 
soma  scrutator),  and  in  fact  one  of  the  largest  of  the  family,  is  a 
brilliant  metallic  green,  bordered  with  a  dark  purplish-blue,  and 
has  the  good  quality  of  having  a  very  particular  appetite,  causing 
it  to  kill  large;  numbers  of  caterpillars,  l)ut  eating  only  part  of  each. 
While  in  the  earth  as  pupa)  large  numbers  of  the  Colorado 
potato-beetles  are  destroyed  by  members  of 
this  family,  and  one  species,  Lehia  grandis, 
which  is  peculiar  in  that  the  wing-covers  are 
somewhat  a]3breviated,  thus  leaving  the  tip 
of  the  alidomen  exposed,  has  been  noticed  on 
the  plants  eating  the  eggs  and  young  larvie  of 
this  old  potato  pest. 

Another  valuable  species  is  one  called  by 
Dr.  Riley  the  Murky  Ground-beetle  (Harpalus  caliginosus) .  Its 
larva  is  of    considerable    assistance   to   fruit-growers   by   eating 


Fig.  9. — Lebia  gran 
dis.   (After Riley.) 


Fig.    10. — The  murky   gmuiul-beetlc   {Harpalus  caliginosus):  adult    at  left; 
a,  larva;  b,  head  of  same;  c,  mandible.     (After  Riley.) 


large  numljcrs  of  curculio  larvie,  which  it  secures  from  the  plums 
after  they  have  fallen  to  the  earth.  From  a  glance  at  its  formid- 
able jaws.  Fig.  10,  b-c,  it  is  easy  to  conjecture  the  fate  of  many  a 
curculio  grub. 


BENEFICIAL  INSECTS,   PREDACEOUS    AND  PARASITIC     17 


Thus  here  again  are  found  some  "bugs"  that  are  friends  and 
not  foes,  worthy  of  all  the  protection  that  can  be  afforded  them, 
and  well  repaying  such  careful  observation  of  their  habits  as  may  be 
bestowed  upon  them. 

Insect  Parasites 

Though  large  numbers  of  injurious  insects  are  annually  de- 
stroyed by  those  which  are  purely  predaceous  upon  them,  many 
more  succuml^  to  those  minute  forms  which  live  parasitically 
within  them.  A  few  of  these  pai'asites  belong  to  the  order  Dip- 
tera,  or  true  flies,  but  most  of  them  are  classed  in  the  order  Hymen- 
optem,  in  which  order  are  also  included  the  saw-flies,  ants,  wasps, 
and  bees. 

Of  the  half-dozen  families  of  hymenopterous  parasites  one  of 
the  largest  and  most  beneficial  is  that  of  the  Ichneumon-flies. 
The  illustrations  will  best  show  the  form  and  structure  of  these 
insects,  which  the   casual 
observer    will    hardly    be 
able  to    disti-nguish    from 
other  families  of  the  group. 
But  it  will  be  noticed  that 
the  fine  veins  of  the  wings 
vary  consideral)ly  in    the 
different  parasites  figured, 
and  it  is  by  these  that  the 
entomologist     is    enabled 
to  separate   the  different 

groups  and  often  to  iden-  ^^'^-  H.— Maggots  of  Pnnjdn  inquisitor,  a 
, -f     ,,  .         ^        ,  parasitic  Iclineum on-fly,  feeding  on  a  cater- 

tify  the  species  at  a  glance.     piUa,.  which  had  spun  its  cocoon  and  was 
Both  this  and   the  follow-     ready  of  pupate, 
ing  family  are  peculiar  in 

having  an  exceedingly  long  ovipositor  or  egg-tube,  of  which  they 
make  a  very  good  use.  It  is  with  this  extensile  tube  that  the 
female  deftly  punctures  the  skin  of  some  unsuspecting  cater- 
pillar, and  under  it  inserts  her  eggs.  In  a  few  days  there  hatch 
from  these  a  host  of  young  maggots  which  feed  upon  the  juices  and 


18         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


tissues  of  the  caterpillar,  but  nre  seemingly  careful  to  avoid  injur- 
ing any  of  its  vital  organs,  for  as  soon  as  the  caterpillar  reaches 
its  full  growth  it  changes  to  a  pupa,  apparently  unaffected. 
When  the  maggots  have  reached  their  full  size  each  spins  up  a 
small  silken  cocoon  inside  the  pupa,  entirely  filling  up  its  now  dead 
shell,  and  instead  of  a  beautiful  moth  appearing  in  the  spring, 
a  horde  of  small  flies  are  seen  to  emerge  from  a  round  hole  in  the 
side  of  the  pupa,  or  cocoon. 

Thus  large  numbers  of  such  pests  as  the  apple-tree  tent-cater- 
pillar (Clisiocampa  ameri- 
cana),  bagworms  (Thyridop- 
teryx  ephemerceformis) ,  cater- 
pillars of  the  swallow-tailed 
l)utterflies  which  feed  upon 
parsley,  carrots,  etc.,  and  a 
host  of  others,  are  consumed 
by  members  of  this  family. 

Those  belonging  to  the 
genus  Ophion  are  partial  to 
the  large  American  silkworms 
which  produce  some  of  our 
largest  and  most  ])eautiful 
moths,  and  difficulty  is  fi'e- 
(juently  experienced  in  I'ear- 
ing  a  desired  number  of  moths 
on  account  of  the  large  per 
cent  of  cocoons  parasitized. 
The  species  of  the  family 
Braconidce  are  very  similar  to 
those  of  the  preceding  one,  and  contain  some  equally  beneficial 
insects,  feeding  as  they  do  upon  such  pests  as  the  codling  moth, 
webworms,  plum-curculio  grubs,  plant-lice,  etc.  Some  of  the  more 
common  foi-ms  of  this  family  belong  to  the  genus  Microgaster,  and 
their  small  white  cocoons  may  frequently  be  seen  almost  covering 
one  of  our  large  tomato-  or  tobacco-worms  (see  page  234),  the  pupa? 
of  which  are  often    known  as  "horn-blowers."     Many  mistake 


Fig.  12. — The  long-tailed  Ophion  {Ophion 
macrurum).       a,    advilt;     b,    maggot; 
enlarged.    (After  Riley.) 


BENEFICIAL  INSECTS,  PREDACEOUS   AND  PARASITIC     19 


these  cocoons  for  the  eggs  of  the  worms,  and  therefore  destroy 
some  of  their  best  friends.     Though  some  thus  spin  their  cocoons 
on  the  outside  of  the  host,  others  remain  inside  of  the  parasitized 
insect  until    the    adult  fly 
emerges.     Thus  dead  plant- 
lice  may  often  be  found  with 
a  large  round  hole  in  the  ab- 
domen— the  onl}'  evidence, 
of  where  one  of  these  para- 
sites has  emerged.     For  this 
reason  dry,  shrunken  plant- 
lice    should    never    be    de- 
stroyed. 

The  Chalcis-flies,  which 
comprise  another  closely  re- 
lated family,  are  exceedingly 
minute  insects,  sometimes 
not  over  one  one-hundredth  Fig.  13.— A  plant-louse  parasite  (Aphidius 
of  an  inch  lono-.  They  are  avenaphis) , showing  above  the  parasitized 
'^       IT    I'l  louse  from  which  it  has  issued.      (Copied 

generally  of  a  metallic  black       from  J,  B.  Smith.) 

color,  and  the  usual  veins  of 

the  wings  are  almost  entirely  absent.  Many  of  these  flies  are 
parasitic  upon  plant-lice,  while  a  large  number  of  their  larvae  live 
and  mature  in  the  eggs  of  other  insects. 

Very  similar  to  the  chalcis-flies  in  their  habits  of  infesting 
plant-lice  and  insect  eggs  are  some  even  smaller  insects — in  fact 
the  smallest  known,  the  largest  being  rarely  over  one-twenty-fifth 
and  the  smallest  only  six-  or  seven-  one-thousandths  of  an  inch  in 
length — with  a  correspondingly  tremendous  and  unpronounceable 
name,  known  to  science  as  the  Proctotrypidcc. 

During  the  last  half  century  the  American  farmer  has  been 
compelled  to  contend  with  an  increasing  number  of  insect  pests, 
which  now  and  then  have  become  veritable  scourges.  Every  now 
and  then  we  hear  of  communities  assembling  for  prayer  and  fasting 
to  appease  the  Almighty,  whose  wrath  has  hurled  a  new  insect 
plague  against  them,  but  such  a  procedure  is  b}-  no  means  as  com- 


20         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

mon  as  formerly,  and  little  reflection  will  show  that  these  scourges 
are  entirely  due  to  natural  causes.  In  fact  they  are  very  largely 
brought  about  by  man  himself.  Some  of  these  pests  are  due  to  the 
fact  that  in  trying  to  subdue  nature  by  clearing  and  cultivating  the 
land,  man  has  deprived  the  insects  of  their  natural  food  plants. 
They  must,  therefore,  needs  feed  upon  that  which  is  substituted 
by  him,  and  as  it  is  less  abundant  than  the  former  wild  vegeta- 
tion, the  number  of  insects  and  the  inj  ury  they  inflict  are  more 
apparent. 

By  far  the  larger  number  of  our  worst  pests,  however,  are  those 
which  come  to  us  from  foreign  shores.  Foreign  insects  are  con- 
stantly being  imported  in  one  way  or  another,  sometimes  being 
already  established  pests  in  other  lands  and  sometimes  only  becom- 
ing so  under  their  new  surroundings.  These  are  even  moi-e  injuri- 
ous than  those  native,  for  whereas  many  of  our  native  birds,  in- 
sects, and  diseases  constantly  prey  upon  native  insects  and  thus 
keep  their  numbers  in  check,  the  enemies  of  imported  pests  rarely 
accompany  them,  and  they  thus  increase  at  an  alarming  rate  and 
do  enormous  damage  before  they  are  attacked  by  the  natural 
enemies  of  similar  native  pests.  It  is  in  the  case  of  these  imported 
pests  that  the  value  of  parasitic  and  predaceous  insects  is  most 
apparent.  In  an  effort  to  make  use  of  them  to  fight  the  gypsy 
and  brown-tail  moths  in  New  England,  the  U.  S.  Bureau  of  Ento- 
mology has  for  several  years  been  importing  large  numbers  of  the 
parasites  and  predaceous  enemies  of  these  pests  and  liberating 
them  in  affected  regions,  thus  carrying  on  a  practical  experiment 
on  a  large  scale  which  may  show  the  importance  of  these  parasites 
in  combating  imported  pests. 

Even  with  our  native  pests,  however,  we  have  frequent  exam- 
ples of  the  value  of  parasitic  and  predaceous  enemies.  Thus  the 
southern  grain  louse,  or  "green  bug,"  was  soon  brought  under 
control  by  the  myriads  of  little  parasites  which  preyed  upon  it 
(see  page  155),  and  these  were  artificially  transported  for  some 
distance  and  liberated  in  large  numbers.  Though  these  efforts  at 
the  distribution  of  this  parasite  may  be  open  to  some  question 
as  to  their  effectiveness,  other  parasites  have  been  successfully 


BENEFICIAL  INSECTS,  PREDACEOUS  AND    EARASITIC     21 

distributed,  and  there  can  be  no  question  that  before  long  we 
shall  come  to  better  understand  how  we  may  make  use  of  these 
valuable  allies,  and  some  day  we  may  be  able  to  duplicate  the 
apparent  miracle  by  which  Dame  Nature  sweeps  away  an  insect 
plague  in  a  few  da3's  with  the  aid  of  these  apparently  insignificant 
parasites. 


CHAPTER    III 


STRUCTURE  AND   DEVELOPMENT  OF  INSECTS 

The  more  experience  the  farmer  has  with  insect  pests,  the 
more  he  comes  to  realize  that  if  he  would  successfully  combat 
them,  he  must  have  a  certain  amount  of  necessary  knowledge 
concerning  their  structure  and  growth. 

•  In  general,  the  artificial  means  which  may  be  effectually 
used  to  combat  an  insect  pest  will  depend  more  or  less  upon 
the  anatomical  structure  of  the  insect,  while  control  by  general 
methods  of  culture  will  depend  upon  a  knowledge  of  the  peculiar- 
ities of  its  life-histor}'.  The  value  of  a  proper  understanding  of 
these  important  factors  in  insect  control  is  therefore  apparent. 

General  Structure  of  an  Insect 
The  body  of  an  insect  is  composed  of  three  separate  parts, 

the  head,  thorax,  and  abdomen 
(Fig.  14),  each  of  which  is  com- 
posed of  several  rings  or  segments. 
To  the  head  are  attached  the 
jointed  antenna?,  or  feelers,  the 
compound  eyes,  and  the  mouth- 
parts,  which  are  described  below. 
Each  of  the  three  segments  of 
the  thorax  Ijears  a  pair  of  legs, 
and  adult  insects  usually  possess 
one  or  two  pairs  of  wings  upon  the 

Fig.  14.-Houey-bee,  showing    the    ^^st  two  segments  of   the   thorax, 
three  principal  regions  of  the  body   The  abdomen  is  composed  of  nine 


of  an  insect: — h,  head;fA,  thorax; 
abd,  abdomen. 

the  females  of  certain  orders. 


or   ten  segments,    but    bears    no 
appenda^s-  save.  fJie  ovipositor  of 


22 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS  23 

Harvest-mites,  or  "  daddy-long-legs,"  sow-bugs,  thousand- 
legged  worms,  and  similar  vermin  are  often  popularly  called 
insects,  but  all  of  them  can  readily  be  distinguished  from  true 
insects  by  their  jjossessing  more  than  six  legs,,  the  ha^vest-miteS 
and  spiders  having  eight  and  the  others  many  more. 

How  Insects  Grow 

With  rare  exceptions  insects  hatch  from  eggs  laid  b}'  the 
adu't  females.  Upon  hatching  they  are  but  little  larger  than 
the  eggs,  and  often  bear  but  little  resemblance  to  their  parents. 
Thus  the  young  caterpillar  would  never  l)e  recognized  as  the 
immature  stage  of  the  butterfly  by  one  unfamiliar  with  its  transfor- 
mations. Grasshoppers  and  some  other  insects,  however,  upon 
hatching  from  tiie  egg  bear  a  marked  resemblance  to  the  adult 
form,  except  that  they  lack  wings. 

Complete  Metamorphosis. — When  the  caterpillar  hatches 
from  the  egg  it  at  once  commences  to  feed  and  grows  very 
rapidly,  liut  1)efore  long  an  obstacle  to  further  growth  arises. 
Unlike  higher  animals,  insects  possess  no  internal  skeleton  or 
framework  for  the  organs  of  the  body,  but  the  outer  skin  becomes 
hardened  and  to  it  the  muscles  and  ligaments  are  attached.  This 
hardening  of  the  skin  is  best  seen  in  the  horny  wing-covers  of  the 
beetles,  and  is  due  to  the  secretion  of  a  hard  substance  called 
chitin.  This  chitin  is  secreted  by  all  parts  of  the  skin  in  greater 
or  less  degree,  and  thus  forms  a  sort  of  shell  for  the  whole  body. 
Though  this  hardening  is  not  so  apparent  in  larvae  as  in  adult 
insects,  it  is  always  present,  and  it  is  for  this  reason  that  when  the 
young  caterpillar  has  made  a  certain  growth  it  is  forced  to  shed  its 
skin,  which  refuses  to  expand  further,  in  order  to  develop  more 
fully.  Thus  the  skins  of  insects  are  shed  several  times  (see  Fig.  15, 
6), — usually  five  or  six,  but  sometimes  as  many  as  twenty,  this 
process  being  known  as  moltinj.  During  its  life  as  a  caterpillar, 
which  is  called  the  larval  slaje,  and  during  which  it  is  called  a 
larva,  it  is  an  elongate,  worm-like  creature,  with  six  short, 
jointed  legs  on  the  three  thoracic  segments,  a  pair  of  fleshy  false 
legs  or  pro-legs  on  the  last  abdominal  segment,  and  probably 


24         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

several  pairs  of  pro-legs  between  these  and  the  true  legs.  No 
traces  of  wings  can  be  seen,  but  the  body  is  often  covered  with 
hairs,  spines,  or  warty  tubercles. 

With  the  next  molt  the  insect  changes  in  appearance  most 
radically,  becoming  a  'pu'pa,  or  chrysalis,  as  this  stage  is  termed 


Fig.  15. — Complete  metamorphosis.  The  different  stages  of  the  com  ear- 
worm  (Heliothis  obsoleta  Fab.):  a,  eggs  on  corn-silk;  b,  the  first  tnree 
larval  stages;  c,  pupa  from  below;  d,  same  from  above;  e,  adult  moth — 
all  enlarged;  b,  about  twice  natural  size, 

for  butterflies.  During  the  pupal  stage  the  insect  remains 
dormant  either  in  a  small  cell  slightly  under  the  surface  of  the 
earth,  or  in  a  silken  cocoon  spun  l^y  the  caterpillar,  or  merely 
attached  to  the  food-plant  by  a  strand  of  silk  or  the  cast  larval 
skin.  In  many  of  the  Diptera, — the  order  including  flies,  mos- 
quitoes, gnats,  etc., — however,  the   last   larval  skin  is  not  shed, 


STRUCTURE  AND    DEVELOPMENT   OF  INSECTS 


25 


but  hardens  and  forms  a  case — called  a  puparium — within  which 
the  pupal  stage  is  passed. 

The  typical  pupa  (Fig.  15,  c,  d)  of  a  butterfly  or  moth  re- 
sembles neither  the  adult  insect  nor  the  larva,  is  of  a  more  or 
less  oval  shape,  with  the  wings  and  antenna  tightly  folded  at 


Fi; 


16.^ — Incomplete  metamorphosis   of  a   bug   {Brachymena  ■i-pusttilata) : 
a,  eggs;  b,  adult  bug;  c,  different  stages  of  young  bugs  or  nymphs. 


the  sides,  the  legs  drawn  up  snugly  together  under  them,  and  the 
head  and  mouth-parts  bent  upon  the  breast,  or  sternum,  though 
all  of  these  parts  are  not  always  recognizable,  the  legs  and  mouth- 
parts  being  sometimes  lacking.  Gradually  the  adult  insect 
develops,  and  at  last  the  pupal  skin  is  broken  open  and  the  airy 
l)\itterfly  emerges  to  enjoy  a  short  life  and  perpetuate  the  species. 


26         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Such  a  series  of  transformations  is  that  commonly  found  among 
butterflies  and  moths  (Lepidoptera),  beetles  (Coleoptera),  flies 
(Diptera),  and  bees  (Hymenoptera),  and  is  known  as  a  complete 
metamorphosis.  All  of  these  insects  normally  pass  through 
four  stages,  of  egg,  larva,  pupa,  and  adult. 

Incomplete  Metamorphosis. — In  contrast  to  this  mode  of 
development  is  that  of  the  grasshoppers  (Orthoptera),  bugs 
(Hcmiptera),  and  some  other  insects.  As  already  stated,  these 
are  much  like  the  adult  upon  emerging  from  the  egg.  With 
each  molt  they  become  larger  and  small  wing-like  pads  gradually 
appear  on  the  sides  of  the  thorax.  There  is  no  dormant  or  pupal 
stage,  the  adult  insect  differing  from  the  previous  stages  in  hav- 
ing fully  developed  wings,  being  larger,  and  often  by  an  accompany- 
ing change  of  markings.  The  immature  stages  of  such  insects 
are  called  nymphs,  and  this  development  an  incomplete  meta- 
morphosis, having  but  three  stages,  of  egg,  nymph,  and  adult 
(Fig.  16). 

The  time  occupied  l)y  the  complete  life-c}'cle  of  an  insect 
varies  from  a  week  or  ten  days  for  the  plant-lice  to  thirteen  or 
seventeen  years  for  some  cicadas,  and  is  entirely  dependent 
upon  the  habit  of  the  species  and  the  climate.  A  correct  knowl- 
edge of  the  exact  time  and  conditions  under  which  the  trans- 
formations occur  for  each  individual  insect  pest  is  therefore  often 
most  essential  when  seeking  means  for  its  control. 

How  Insects  Feed 

The  material  to  l^e  used  in  combating  a  given  insect  is  largely 
dependent  upon  the  structure  of  its  mouth-parts.  Much  Paris 
green  is  wasted  upon  insects  unable  to  eat  it  and  which  it  will, 
therefore,  never  kilL 

Insects  may  be  roughly  divided  into  two  classes,  those  which 
bite  and  those  which  suck  their  food.  Among  the  fornun-  are 
the  beetles,  grasshoppers,  the  larva)  of  Ijutterflies  and  moths, 
and  the  larvae  of  saw-flies ;  and  among  the  latter  are  butterflies, 
flies,  bees,  and  bugs,  while  the  larvae  of  most  flies  and  bees  do  not 
possess  mouth-parts  homologous  with  those  of  the  above.. 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 


27 


Biting  Mouth-parts. — 
insects  are  easih'  seen 
in  the  grasshopper 
(Figs.  17  and  IS).  In 
brief,  they  consist  of  an 
upper  and  a  lower  lip, 
between  which  are  two 
pairs  of  jaws  which 
work  transversely.  The 
upper  pair  of  jaws,  or 
mandibles  (7nd.),  are 
stout,  short,  and  horny, 
usually  sharpened  at 
the  tip,  slightly  serrated 
at  the  margins,  and  j 
flattened  at  the  base. 
The  lower  pair  of  jaws, 
or  maxilhc  (nix.),  are 
longer,  not  so  strong, 
and  to  each  of  them  is  at 


Mouth-parts  typical  of  those  of  biting 


iG.  17. — Front -view  face  of  grasshopper  {Schizto- 
cerca  americana):  ant.,  antenna;  oc,  ocellus; 
eij.,  eye;  cl.,  clypeus;  Ibr.,  lahrum,  or  upper 
lip;  w.r./)..  maxillary  palpus;  Zah./).,  labial  pal- 
pus; gal.,  galea,  lobe  of  maxilla;  lab.,  labium,  or 
under  lip. 

tached  an  accessory  lobe,  and  a  jointed 

B 


hiip. 


Fig.  18. — .4,  mouth-parts 
of  grasshopper  sep- 
arated to  show  posi- 
tion and  relation;  B, 
mouth-parts  dissect- 
ed; Ihr.,  labrum;  md., 
mandil)lc;  hyp.,  hypopharynx  or  tongue;  mx.p. 
Ih.  p.,  labial  palpus;  lab.,  labium;  max.,  maxilla}.. 


maxillary    palpus; 


28        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


style  called  a  palpus  or  feeler.     At  each  side  of  the  lower  lip  is 

another  palpus,  these  palpi   being 
sensory  organs. 

Sucking  Mouth-parts. — In  the 
sucking  insects  these  mouth-parts 
are  prolonged  into  a  tube  through 
which  the  juices  of  the  food  plant 
— or  animal — are  sucked.  In  the 
plant-lice  and  other  bugs  the  lower 
lip  is  elongated  so  that  it  forms  a 
tube,  and  the  maxillae  and  man- 
dibles consist  of  long  hair-like 
bristles,  or  setse,  enclosed  within 
this  tube  (Fig.  20).  The  tip  of  this 
beak  is  rested  upon  the  surface  of  a 
leaf  into  which  the  setse  are  thrust, 
lacerating  the  tissue,  and  by  a 
pumping  process  of  the  mouth  the 
juices  are  sucked  up  through  the 
beak.  The  structure  of  the  mouth- 
parts  of  the  various  orders  of  suck- 
ing insects  varies  considerably,  but 
all  agree  in  that  they  suck  up  the 
food  in  a  liquid  state.  Any  appli- 
cation of  a  poisonous  spray  to  the 
surface  of  foliage  will  be  of  no  avail 
parts  of  "a  bug,' a  sucking  insect :  against  them,  though  sure  death  to 
a,  seen  from  below,  beak  or  ^^^^  biting  insects  which  chew  the 
rostrum    {ro.  G.)    reposing     be-  n      i  •        •  ^  .  ^  i 

tween  forelegs;  h,  head  removed :  leaves.     Suckmg  msects  must  there- 
e,  eye;   Ihr.,  labrum;  md.,  man-  fore  be  killed  by  other  means, 
dible-setse;  rnx.,  maxillary  setse; 
lah.,  labiimi. 

How  Insects  Breathe 

Along  the  side  of  a  caterpillar  or  larva,  on  one  thoracic  seg- 
ment and  on  each  abdominal  segment  except  the  last,  is  a  small 
oval  spot,  in  the  centre  of   which  is  a  slit  closed  by  two  mem- 


FiG.  19. — Cicada,  showing  mouth- 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS 


29 


Fig.  20. — Mouth-parts  of  a  plant- 
louse:  a,  the  jointed  beak;  h,  the 
lancets,  much  enlarged ;  c,  antenna; 
d,  foot.     (After  J.  B.  Smith.) 


Fig.  21 . — Diagram  of  tracheal 
or  breathing  system  of  an 
insect:  sp.,  spiracles;  tr., 
trachea.     (After  Kolbe.) 


Fig.  22. — Ideal  section  through  an  insect:  a,  aUmentary  canal;  h,  heart; 
n,  nerve  cord;  s,  spiracle;  t,  tracheal  tubes;  I,  legs;  w,  wings.  (From 
Riverside  Natural  History.) 


30 


INSECT  PESTS  OF    FARM,  GARDj^N  AND   ORCHARD 


branous  lips.  These  apertures  arc  called  spiracles  or  stigmata 
(Fig.  21  sp.),  and  are  the  openings  of  the  respiratory  system. 
Similar  openings  are  to  be  found  in  all  insects,  though  not  so 
easily  seen  in  the  adults.  Connecting  these  spiracles  is  a  pair  of 
tubes  on  each  side  of  the  body,  throughout  its  length,  from  which 
branch  off  smaller  tubes  to  all  of  its  organs  and  tissues.     Fresh 


n.    sp 


Fig.  23. — Internal  anatomy  of  silk-worm,  from  photo  of  Azoux  Model: 
A ,  upper  or  dorsal  bodywall  seen  from  within ;  B,  the  back  of  the  silk- 
worm removed,  showing  alimentary  canal;  C,  alimentary  canal  removed, 
showing  nervovis  system  and  tracheal  trunks;  tr.,  trachea;  d.v.,  dorsal 
vessel  or  heart;  ph.,  pharynx  or  mouth;  su.,  supra-oesophageal  ganglion; 
sp.sp.,  spiracles  or  breathing  pores;  n.,  nerve  cord;  tr.t.,  tracheal 
trunk;  oes.,  oesophagus  or  throat;  cr.,  crop;  s.g.,  silk  gland;  pro., 
provcntriculus ;   st.,  stomach;   h.i.,  hind  intestine. 

air  is  thus  inhaled  to  all  parts  of  the  body  through  these  tubes 
(Fig.  21,  tr). 

The  l^lood  of  insects  does  not  circulate  through  any  system  of 
tubes  as  it  does  in  the  higher  animals.  Along  the  middle  of  the 
back,  above  the  alimentary  canal,  is  a  long  tube  popularly  called 
the  heart  (Fig.  23,  dv).  This  heart  is  composed  of  a  number  of 
chambers,  each  of  which  is  furnished  with  side  valves  for 
admitting  blood  from  the  body-cavity.  The  blood  coming 
into  the  heart  from  the  body-cavity  is  propelled  forward  toward 


STRUCTURE  AND  DEVELOPMENT  OF  INSECTS  31 

the  head,  where  it  again  flows  into  the  body-cavity.  Thus  various 
currents  of  blood  are  maintained  throughout  the  body,  but  other 
than  the  heart  there  is  no  system  of  blood-vessels,  the  blood  merely 
filling  the  body-cavity  around  and  through  the  various  organs  and 
tissues.  Constantly  flowing  around  the  respiratory  tubes  or 
trachea:^,  the  l)lood  is  quickly  and  thoroughly  purified,  though  the 
exact  manner  in  which  this  is  done  is  not  definitely  known.  The 
respiratory  system  has  absolutely  no  connection  with  the  mouth 
or  pharynx  (Fig.  23,  ph),  as  have  the  lungs  of  the  higher  animals, 
and  if  an  insect  is  to  be  suffocated,  it  must  be  done  by  closing  the 
spiracles.  It  is  in  this  way  that  tobacco-clust,  lime,  pyrethrum, 
and  similar  insecticides  kill  sucking  insects,  by  penetrating  the 
spiracles  and  choking  the  tracheal  system.  Whale-oil  soap, 
kerosene  emulsion,  and  the  other  "  contact  "  insecticides,  or  "  irri- 
tants," also  stop  up  the  spiracles  and  thus  cause  death,  but  they 
may  act  as  "  irritants,"  penetrating  the  skin  and  thus  killing  the 
insect.  When  insects  are  killed  by  means  of  a  gas  such  as  carbon 
bisulfide  or  h3'drocyanic  acid  gas,  they  are  asphyxiated  by  a 
substitution  of  these  gases  for  air,  the  same  as  are  the  higher 
animals. 

The  ugh  arsenical  poisons  are  generally  used  as  sprays  for  biting 
insects,  soft-bodied  caterpillars  and  similar  larva?  are  often  killed 
by  the  use  of  contact  insecticides,  which  affect  them  the  same  as 
sucking  insects. 

The  reader  will  observe  that,  almost  without  exception,  the 
remedies  advised  for  different  insect  pests  in  the  following  pages 
are  determined  by  some  peculiarity^  either  of  structure  or  develop- 
ment, of  the  insect  to  be  combated. 


CHAPTER  IV 
FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS 

The  old  adage  "  an  ounce  of  prevention  is  worth  a  pound  of 
cure/'  is  never  more  true  than  in  the  control  of  insect  pests,  for  in 
almost  all  cases  their  successful  control  is  by  prevention  before  the 
injury  has  become  acute,  rather  than  by  destruction  after  the 
injury  is  noticeable.  Even  insecticides  must  be  applied  so  that 
they  will  kill  the  insect  before  it  has  done  serious  damage,  for  after 
damage  is  apparent  it  is  too  late  to  prevent  the  injury,  so  that 
the  use  of  insecticides  for  the  protection  of  crops  must  be  of  a  pre- 
ventive nature.  In  the  control  of  insects  affecting  the  staple 
crops  which  are  grown  over  immense  areas  with  a  small  profit  per 
acre,  it  is  evidently  impracticable  to  use  insecticides  and  mechani- 
cal methods  which  are  used  in  the  orchard  and  garden.  For  the 
control  of  staple  crop  insects  we  are  compelled  to  rely  largely  on 
general  methods  of  farm  management,  which  may  be  carried  out 
in  connection  with  the  farm  operations  at  small  cost,  and  which 
will  fatally  interfere  with  the  development  of  the  insect  to  be  con- 
trolled. To  do  this  intelligently  involves  an  understanding  of 
the  life-history  of  the  insect,  revealing  the  time  at  which  it  is  most 
vulnerable  and  the  reason  for  the  method  of  control  advised.  The 
importance  of  such  a  knowledge  of  the  life  histories  and  habits  of 
insects  to  be  controlled  by  farm  methods  will  become  apparent 
in  the  following  chapters. 

Though  the  insects  affecting  staple  crops  are  more  largely  con- 
trolled by  farm  methods,  those  of  the  garden  and  orchard  may  be 
much  reduced  by  the  intelligent  application  of  the  same  princi- 
ples, and  he  who  adapts  his  methods  so  as  to  prevent  insect  attack 
will  be  much  more  successful  than  if  he  depends  upon  artificial 
means  for  their  destruction. 

32 


FARM   METHODS  FOR  THE   CONTROL  OF  INSECTS        33 

Looking  Ahead. — In  planning  the  management  of  their  land 
and  crops  for  the  coming  season,  few  farmers  consider  the  effect 
which  any  given  procedure  will  have  upon  the  injurious  insects  with 
which  they  may  have  to  contend.  A  field  which  has  for  several 
years  been  in  wheat,  corn,  or  tobacco,  may  be  sown  with  some 
other  crop  for  the  sake  of  soil  improvement,  but  how  often  is  it 
considered  necessary  to  rotate  crops  to  avoid  insect  pests?  In 
most  cases  they  are  left  out  of  consideration  vmtil  a  crop  has  been 
seriously  injured  and  the  necessity  for  a  change  of  methods  thus 
impressed  on  the  owner. 

Particularly  while  crops  are  young  they  should  be  frequently 
inspected  and  examined  for  any  evidence  of  the  pests  which  com- 
monly affect  them.  Be  prepared  to  attack  any  pests  which 
may  be  found  upon  their  first  appearance,  for  many  of  the 
most  destructive  insects  increase  with  amazing  rapidity,  and 
when  they  have  become  abundant  it  is  too  late  to  prevent  the 
damage. 

Cwp  Rotation. — One  of  the  most  important  factors  in  insect 
control  is  the  rotation  of  crops  in  such  a  manner  that  the  same 
crop  shall  not  be  grown  continuously  on  the  same  land.  In  many 
cases  a  yearly  rotation  will  be  advantageous,  while  a  frequent 
rotation  will  always  be  found  beneficial.  Many  insects  feed  on 
only  one  crop.  It  is  evident,  therefore,  that  if  they  hibernate  in 
or  near  the  field  which  it  occupied  and  it  is  then  planted  to  the 
same  crop  the  next  year,  they  will  be  furnished  food  for  their 
increase,  while  if  the  field  be  planted  in  a  crop  not  attacked  by 
the  insects  peculiar  to  it,  they  will  have  to  migrate  from  it,  with 
probably  a  very  considerable  mortality  as  a  consequence,  for  they, 
will  radiate  in  all  directions  and  many  will  die  before  finding  food, 
while  many  more  will  have  been  destroyed  in  the  preparation  of 
the  old  field  for  the  new  crop. 

The  western  corn  root-worm  may  be  entirely  controlled  by  a 
rotation  so  that  corn  is  never  grown  two  successive  years  on  the 
same  land;  for  the  larvae  feed  only  on  the  roots  of  corn,  and  when 
it  is  followed  by  a  small  grain,  grass,  or  clover,  they  are  starved 
out.     Injury  by  the  Hessian  fly  to  wheat  is  also  very  materially 


34         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

reduced  where  a  frequent  rotation  is  practised,  as  is  that  of  the 
chinch-bug  on  corn. 

Care  should  be  exercised  to  arrange  a  rotation  in  which  crops 
nearly  related  botanically  do  not  follow  each  other,  for  usually 
the  same  insects  attack  them.  Thus  white  grubs,  cutworms, 
and  wireworms  live  normally  in  grass  land,  and  where  it  has  not 
been  plowed  for  several  years  they  often  become  exceedingly 
abundant.  If  the  sod  be  then  turned  under  and  the  land  planted 
to  corn  these  insects  will  attack  the  corn,  and  as  there  are  rela- 
tively few  plants  to  the  number  of  insects  which  were  feeding 
upon  the  grass,  the  injury  will  usually  be  serious.  To  avoid 
this,  sod  land  should  be  planted  in  a  small  grain,  buckwheat, 
potatoes,  or  some  crop  not  affected  by  these  pests.  Similarly, 
the  insects  which  affect  cabbage  usually  feed  on  all  the  cole  crops, 
and  turnips,  radishes,  etc.,  following  cabbage  will  be  liable  to 
injury  by  the  same  pests.  Clovers,  cowpcas,  and  other  leguminous 
crops  become  of  importance  in  rotation  in  this  connection,  as 
they  are  not  usually  attacked  by  the  insects  affecting  other  crops, 
and  of  course  are  widely  used  in  every  good  rotation  for  the  pur- 
pose of  storing  nitrogen  in  the  soil  through  their  root  tubercles. 

Time  of  Planting. — Planting  crops  so  that  they  may  avoid 
the  greatest  abundance  of  their  worst  insect  enemies  is  often  the 
best  method  for  their  protection.  Thus  late-sown  wheat  is 
usually  exempt  from  the  attack  of  the  Hessian  fly  (see  page  123) 
and  late-planted  corn  is  much  less  affected  by  the  stalk-borer 
(see  page  172)  than  that  planted  earlier.  On  the  other  hand 
early  planting  of  early-maturing  varieties  often  enables  the  crop 
to  mature  Ix'fore  its  pests  become  most  aJjundant.  Thus  early 
planting  and  early  varieties  are  of  the  greatest  importance  in 
preventing  injury  by  the  cotton  boll  weevil,  the  cotton  boll- 
worm  and  corn  ear-worm.  Early  cabbage  plants  seem  to  be  less 
injured  by  root-maggots,  and  early  varieties  of  peas  escape  the 
injury  of  the  pea  aphis. 

Weeds. — Many  insects  feed  upon  some  common  weed  in  one 
stage  while  in  another  stage  they  are  injurious  to  a  cultivated 
crop.     Thus  the  flea-beetles  feed  upon  the  roots  of  solanaceous 


FARM  METHODS  FOR  THE  CONTROL  OF    INSECTS        35 

weeds  during  the  larval  stage,  while  the  adults  attack  all  sorts  of 
garden  crops.  In  many  cases  caterpillars,  such  as  the  salt  marsh 
caterpillar,  army  worms,  the  white-lined  sphinx  moth,  and 
grasshoppers  multiply  upon  weeds  growing  in  neglected  fields 
until  they  overflow  and  destroy  crops.  Many  insects  feed  on 
weeds  during  the  early  part  of  the  season  or  after  the  crop  which 
they  injure  is  harvested,  so  that  the  destruction  of  these  weeds 
may  often  considerably  shorten  their  breeding  season  or  increase 
their  mortality.  Thus  the  corn  root-aphis  lives  on  the  roots 
of  smartweed  and  other  weeds  and  grasses  until  corn  is  available 
and  cutworms  feed  on  whatever  vegetation  is  found  before  a 
crop  is  planted.  In  this  connection  "  volunteer  "  plants  should 
be  classed  as  weeds,  as  they  frequently  furnish  food  for  insects 
in  the  same  way.  Thus  the  cotton  boll  weevil  feeds  on  volunteer 
cotton  in  early  spring  and  the  Hessian  fly  on  volunteer  wheat 
in  late  summer  and  early  fall.  Such  useless  trees  as  wild  cherry 
and  seedling  apple  trees  might  also  be  considered  as  weeds,  as  they 
harbor  many  of  the  insect  pests  of  our  orchards  and  should  be 
destroyed  as  far  as  possible. 

Fertilization  and  Culture. — Although  there  is  some  evidence 
that  under  some  conditions,  kainit,  lime  and  nitrate  of  soda  may 
have  some  direct  effect  on  insects,  it  is  probable  that  their  chief 
importance  is  to  so  stimulate  the  plant  that  it  will  not  be  subject 
to  insect  attack  or  will  grow  in  spite  of  some  injury.  It  is  well 
known  that  plants  which  have  been  weakened  from  any  cause 
whatsoever  are  much  more  subject  to  the  attacks  of  insects  and 
diseases,  and  it  is  therefore  obvious  that  plants  which  have  had  a 
vigorous  growth  and  which  will  mature  rapidly  will  much  better 
withstand  insect  attack.  Thorough  preparation  of  the  soil 
before  planting,  liberal  fertilization,  and  thorough  culture  are 
most  important  in  growing  a  crop  in  spite  of  its  insect  enemies. 
In  many  cases  liberal  fertilization  and  culture  will  mature  a  good 
crop  where  under  poorer  care  it  would  have  succumbed  to  insect 
injury.  In  general,  land  covered  with  barnyard  manure  presents 
more  favorable  conditions  for  the  hibernation  of  insects  than  that 
fertilized  with  mineral  fertilizers,  but  unless  this  is  very  appreciably 


Fig.  24. — Above,  a  poorly  kept  roadside  with  railfence  overgrown  with 
brambles,  thus  affording  protection  for  large  numbers  of  destructive 
insects  during  winter.  Below,  a  well  kept  roadside,  offering  the  least 
protection  possible  for  destructive  insects.  (After  Webster,  U.  S. 
Dept.  Agr.),  36 


FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS 


37 


the  case,   it  will   usually   be   preferred  to  them  as  far  as  it  is 
available. 

Clean  Farming. — After  a  crop  has  been  harvested  there  is 
usually  some  portion  of  the  plant  which  is  allowed  to  remain 
on  the  land.  In  this  refuse  the  insects  peculiar  to  the  crop  often 
feed  and  multiply  until  killing  frost  and  then  hibernate  over 
winter,  ensuring  injury  to  similar  crops  on  the  same  land  the 


Fig.  25. — A  field  of  cabbage  stumps  in    midwinter,  affording  ideal  condi- 
tions for  the  hibernation  of  cabbage  pests. 


next  year.  Thus  the  wheat  joint  worm  and  the  corn  stalk-borer 
l>oth  winter  in  the  stubble  of  those  crops,  and  the  chinch-bug 
commonly  hibernates  in  the  butts  of  corn  stalks,  all  of  which 
may  be  largely  controlled  by  burning  the  stubble.  Possibly 
the  most  important  means  of  control  of  the  cotton  bo-11  weevil 
is  the  destruction  of  the  stalks  in  the  fall  as  soon  as  the  cotton 
can  be  picked,  thus  preventing  the  weevils  feeding  and  starving 
them  out  l^efore  they  are  ready  to  hibernate,  and  removing  the 
shelter  for  hibernation.     Thus  all  the  remnants  of  a  crop  such  as 


38        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

stubble,  vines,  leaves,  or  stumps,  as  may  be,  should  be  removed 
from  the  field  as  soon  after  it  is  harvested  as  possible.  As  many 
insects  hibernate  in  such  rubbish,  this  fact  may  sometimes  be 
utilized  by  thoroughly  cleaning  a  field  and  leaving  one  or  two 
piles  of  rubbish  in  which  man}'  of  the  insects  will  assemble  for 
hibernation,  and  which  ma}*  then  be  burned  or  otherwise  destroyed. 
Many  cabbage  insects  hibernate  under  the  old  stumps  and  leaves 
and  will  congregate  in  piles  of  them.  The  premises  upon  which 
the  fence  rows  are  kept  free  from  weeds  and  grass  and  the  fields 
are  cleaned  up  antl  plowed  as  soon  as  possible  after  a  crop  is 
removed,  usually  suffer  much  less  from  insect  pests  than  thoo?  of 
more  easy-going  neighbors. 

Burning. — Such  cleaning  up  of  stubble  and  of  wild  vegetation 
which  furnishes  food  and  shelter  for  insects  may  often  be  accom- 
plished bv  burning.  The  burning  over  of  grass  land  aids  greatly 
in  the  control  of  army  worms,  chinch-bugs,  grasshoppers  and 
plant-lice,  while  the  burning  of  the  stubble  will  largely  control 
the  wheat  jointworm.  Strawberry  beds  are  sometimes  burned 
over  in  early  spring  to  destroy  the  eggs  of  the  root-louse,  and 
aphides  on  small  grains  may  sometimes  be  killed  out  on  small 
areas  by  covering  with  straw  and  burning  while  the  plants  are 
small. 

Plowing. — Deep  plowing  and  thorough  harrowing  are  the  most 
effective  means  of  ridding  the  soil  of  many  pests  of  staple  crops. 

Late  Fall  Plowing. — Where  the  succession  of  crops  permits, 
plowing  in  the  late  fall  is  most  advantageous,  as  it  destroys  the 
insects  Avhile  hibernating,  although  for  some  insects ,  early  fall 
plowing  antl  thorough  harrowing  during  the  fall  are  preferable. 
Where  plowing  is  not  possible,  thorough  disking  is  often  used 
for  the  same  purpose,  as  on  alfalfa.  As  different  insects  pass  the 
winter  in  different  stages  this  method  does  not  affect  all  alike. 
Some  will  be  destroyed  by  having  the  cells  in  which  they  have 
gone  to  pass  the  winter  broken  up.  and  l3eing  unable  to  construct 
new  cells  they  will  be  subjected  to  undue  freezing  and  thawing 
and  excessive  moisture,  and  will  thus  be  killed  by  the  weather. 
Cutworms  and  the  corn  stalk-borer  pass  the  winter  in  the  soil 


FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS        39 

as  larvae;  the  cotton  boll  worm  or  corn  ear- worm  hibernates 
in  the  pupal  stage;  while  May  beetles  and  click  beetles  hibernate 
as  newly  transformed  beetles;  but  all  of  them  will  be  similarly 
affected  by  the  breaking  up  of  their  winter  cells,  which  is  the 
most  effective  manner  of  combating  them. 

Other  insects  lay  their  eggs  in  the  ground  in  the  fall  which 
may  be  buried  too  deep  for  the  young  to  emerge,  or  larvae  or  pupae 
which  normally  remain  near  the  surface  may  be  turned  under  so 
deeply  as  to  destroy  them.  Thus  grasshopper's  eggs  are  laid  in 
the  fall  just  beneath  the  surface,  and  by  plowing  in  late  fall  or 
early  spring  they  may  be  turned  under  so  that  but  few  are  able  to 
emerge,  which  is  the  best  means  of  combating  them.  The  apple 
maggot  hibernates  in  the  pupal  stage  just  beneath  the  surface  of 
the  soil,  and  by  deep  plowing  in  early  spring  the  puparia  may  be 
buried  too  deeply  for  the  flies  to  emerge. 

Young  grasshoppers  are  often  destroyed  after  they  hatch  by 
plowing  deep  furrows,  starting  at  the  outside  of  the  field  and  plow- 
ing in  a  square,  thus  forcing  them  to  the  centre  and  catching  large 
numbers  of  them  in  the  furrows. 

Early  plowing  and  thorough  harrowing  in  the  spring  are  of 
value  against  cutworms  by  keeping  the  ground  fallow  and  thus 
starving  them  out  before  a  crop  is  planted  and  the  same  method 
may  be  used  against  other  pests  with  similar  habits. 

Thorough  cultivation  in  the  summer  has  been  found  to  be  of 
value  against  many  insects,  affecting  them  differently  according  to 
their  habits.  Many  which  pupate  in  the  soil  during  the  summer 
are  destroyed  while  making  their  pupal  cells,  or  these  cells  are 
broken  and  they  are  thus  subject  to  abnormal  moisture  and  tem- 
perature conditions  and  are  thus  killed.  This  has  been  shown  to  be 
the  case  with  the  cotton  bollworm  or  corn  ear-worm,  and  is  true 
of  the  plum  curculio,  against  which  thorough  cultivation  has 
proved  to  be  one  of  the  most  effective  means  of  control  in  apple 
orchards.  Thorough  cultivation  is  also  of  importance  in  breaking 
up  the  nests  of  ants  which  care  for  such  aphides  as  the  corn  root- 
aphis.  Summer  fallowing  is  used  to  starve  out  some  pests;  for 
example,  the  clover  root-borer  may  be  eradicated  by  plowing  up 


40        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

infested  clover  iinniecliately  after  it  is  cut  and  exjjosing  the  roots 
to  the  sun  and  wind,  which  will  soon  dry  them  out  and  thus  destroy 
the  food  of  the  larvae,  which  will  soon  perish. 

Trap  Crops. — Trap  crops  are  those  which  are  planted  as  a  bait 
or  lure  to  attract  the  early  insects  so  that  they  may  be  destroyed 
upon  them  before  the  crop  to  be  protected  is  available.  Doubt- 
less the  reason  that  trap  crops  are  not  more  frequently  used  by  the 
farmer  is  because  their  successful  use  requires  more  or  less  of  a 
knowledge  of  the  life  history  and  habits  of  the  pest  to  be  fought. 
But  that  is  easily  acquired  and  will  make  the  fight  against  them 
more  interesting  and  successful. 

South  of  Mason  and  Dixon's  line  the  harlequin  cabbage- 
bug  frequently  becomes  the  most  serious  pest  of  cabbage  and 
related  plants.  When  a  cabbage  patch  has  become  well  infested 
it  is  an  exceedingly  difhcult  matter  to  prevent  injury,  for  the  adult 
bugs  cannot  be  killed  by  insecticides  which  will  not  injure  the 
plant.  If,  however,  a  crop  of  kale  be  planted  the  previous  fall, 
the  bugs  which  hibernate  over  winter  will  attack  it  in  the  spring, 
and  may  then  be  killed  by  spraying  them  with  pure  kerosene,  and 
the  danger  to  the  cabbage  crop  be  thus  largely  averted. 

A  few  rows  of  wheat  are  often  planted  early  in  the  fall  as  a  trap 
for  the  Hessian  fly,  and  as  soon  as  the  eggs  are  deposited  they  are 
plowed  under  deeply  and  the  later  planting  thus  at  least  partly 
protected. 

One  of  the  most  successful  examples  of  averting  injury  ]jy  a 
trap  crop  is  the  use  of  corn  to  lure  the  cotton  bollworm  and  thus 
prevent  its  injury  to  cotton.  Corn  is  the  favorite  food  plant  of 
this  pest,  which  prefers  to  deposit  its  eggs  on  the  silk  and  tassels. 
By  planting  a  few  strips  of  late-maturing  corn  through  the  cotton 
field,  they  will  come  into  silk  about  the  time  the  brood  of  moths 
which  normally  deposit  their  eggs  on  cotton  are  flying  and  they 
will  lay  them  on  the  corn  in  preference,  which  should  then  be  cut 
and  fed  to  stock.  In  this  way  by  planting  strips  composed  of  sev- 
eral rows  planted  at  successive  dates,  the  cotton  may  be  almost 
entirely  protected.  Possibly  a  modification  of  this  method  may 
be  applied  for  the  protection  of  tomatoes  or  tobacco,  though  these 


FARM  METHODS  FOR  THE  CONTROL  OF  INSECTS        41 

cro23s  have  never  been  thus  protected  from  this  insect  to  our 
knowledge. 

Radishes  are  sometimes  used  as  a  trap  crop  for  the  root-mag- 
gots which  affect  the  roots  of  cabbages  and  onions.  The  same 
prhiciple  is  sometimes  used  in  combating  forest  insects  by  gird- 
ling a  tree  upon  which  certain  kinds  of  forest  pests  will  concentrate, 
and  it  is  then  cut  and  burned. 

These  examples  will  suffice  to  show  that  very  many  of  the  most 
important  insect  pests  may  be  largely  controlled  by  simply  adapt- 
ing the  general  methods  of  farm  management  so  as  to  avoid  or 
prevent  injury  by  them.  They  indicate  the  importance  of  a 
knowledge  of  the  life  history  of  any  insect  which  is  to  be  combated, 
knowing  waiich,  some  of  the  above  or  similar  methods  will  often 
suggest  themselves  as  applicable.  Such  a  control  of  insect  life 
through  the  practical  use  of  natural  agencies  epitomizes  the  scien- 
tific method  in  the  art  of  agriculture;  i.e.,  the  most  practical  and 
effective  and  yet  simple  methods  based  upon  exact  knowledge.* 

*  See  F.  M.  Webster,  Farm  Practice  in  the  Control  of  Field  Crop  Insects, 
Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  465,  and  Some  Things  that  the  Grower 
of  Cereal  and  Forage  Crops  Should  Know  about  Insects,  Yearbook  U.  S. 
Dept.  Agr.,  1908,  page  367. 


CHAPTER  V 

INSECTICIDES 

Materials  used  for  the  destruction  of  insects  are  commonly 
called  insecticides,  and  are  roughly  divisible  into  four  classes: 

1.  Poisons,  which  kill  by  being  eaten  and  are  usually  composed 
of  various  forms  of  arsenic  and  are  therefore  often  called  arseni- 
cals. 

2.  Contact  insecticides,  which  kill  by  either  clogging  up  the 
spiracles,  the  openings  of  the  respiratory  system,  or  by  entering 
the  trachea,  and  thus  causing  suffocation,  or  by  their  corrosive 
action  on  the  skin. 

3.  Repellants,  which  deter  the  insect  from  attacking  the  plant 
or  animal  to  which  they  are  applied. 

4.  Gases,  which  are  used  for  fumigating  buildings,  stored  prod- 
ucts and  greenhouses  where  other  means  are  not  practicable. 

1.  Poisons 

Poisons  are  applied  to  the  food  of  the  insect  and  must  be  eaten 
by  it  to  be  effective.  It  is  evident,  therefore,  that  they  are  only 
effective  against  biting  (mandibulate)  insects,  or  for  those  which 
lap  up  their  food  from  the  surface,  and  that  they  are  of  no  avail 
against  the  true  sucking  insects,  such  as  the  true  bugs  which  suck 
the  juices  from  beneath  the  surface  of  the  plant.  Poisons  are  not 
always,  however,  the  most  effective  means  of  combating  biting 
insects,  which  are  sometimes  more  effectively  controlled  by  con- 
tact insecticides  or  other  means. 

Nearly  all  of  the  stomach  poisons  are  derivatives  of  arsenic 

and  are  therefore  termed  arsenicals.     As  they  are  dangerous  to 

human  life  they  should  be  kept  well  labeled,  locked  up  when  not 

in  use,  and  vessels  in  which  they  have  been  used  should  be  care- 

fullv  cleaned. 

42 


INSECTICIDES  43 

1.  Paris  green  is  a  green  crystalline  powder  composed  of  the 
aceto-arsenite  of  copper.  When  properly  made  it  should  contain 
at  least  50  per  cent  arsenic  oxid  (AS2O5),  and  there  should  be  as 
little  water-soluble  arsenic  as  possible,  for  the  water-soluble  arsenic 
is  the  cause  of  the  burning  of  foliage  which  often  results  from  the 
use  of  Paris  green.  \'arious  State  laws  require  that  there  be  not 
over  3J  per  cent  soluble  arsenic,  but  even  this  amount  is  often 
injurious  to  tender  foliage.  Paris  green  is  rather  a  coarse  powder 
and  settles  readily  in  water,  and  is  readily  washed  off  by  drenching 
rains.  It  costs  from  25  to  35  cents  per  pound.  It  is  usually  used 
at  a  rate  of  from  3  to  8  ounces  to  a  50-gallon  barrel  of  water;  5 
ounces  per  barrel  is  satisfactory  for  most  purposes.  In  mixing, 
first  stir  up  in  a  small  vessel  with  a  little  water  into  a  paste,  which 
will  mix  more  readily.  Add  an  equal  weight  of  quicklime,  or 
slightly  more  will  do  no  harm,  which  will  take  up  any  soluble 
arsenic. 

2.  London  purple  is  a  waste  product  in  the  manufacture  of 
aniline  dyes,  and  is  principally  arsenic  and  lime.  It  is  quite 
variable  in  composition  and  usually  contains  a  much  higher, 
and  quite  variable,  amount  of  soluble  arsenic,  so  that  it  is  apt  to 
scald  the  foliage  unless  thoroughly  mixed  with  fresh  stone  lime. 
For  this  reason  it  is  now  used  only  for  rough  work,  such  as  poison- 
ing grasshoppers,  making  poisoned  bran  mash,  etc.,  and  is  not 
to  be  recommended  for  general  use  on  fruit  trees  and  garden 
crops.  It  usually  costs  10  or  12  cents  a  pound,  and  is  used  in 
the  same  proportions  and  in  the  same  way  as  Paris  green. 

3.  Arsenate  of  lead  is  usually  sold  in  the  form  of  a  white  paste, 
composed  of  arsenic  and  lead,  the  exact  chemical  composition 
varying  with  the  process  of  manufacture.  To  be  of  standard 
grade  it  should  contain  at  least  12^  per  cent  of  arsenic  oxid 
and  not  over  f  per  cent  water-soluble  arsenic  oxid  (AS2O5), 
and  not  over  50  per  cent  water.  Owing  to  the  small  amount 
of  soluble  arsenic  it  may  be  used  in  much  larger  quantities  than 
other  arsenicals  and  on  tender  foliage  which  others  will  injure. 
From  2  to  8  pounds  per  50-gallon  barrel  of  water  are  used,  2 
or  3  pounds  per  barrel  being  commonly  used  for  most  of  the 


44        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

pests  of  the  orchard  and  garden.  Arsenate  of  lead  remains  in 
suspension  rather  better  than  Paris  green  and  is  exceedingly 
adhesive,  remaining  on  the  foliage  for  two  or  three  months. 
Arsenate  of  lead  is  made  from  arsenate  of  soda  and  acetate  of 
lead  or  nitrate  of  lead,  and  may  be  made  by  the  user  if  desired, 
but  owing  to  the  varying -composition  of  these  chemicals  when 
purchased  on  the  open  market  and  the  fact  that  the  manufactured 
article  can  now  be  purchased  in  quantity  practically  as  cheap  as 
it  can  be  made,  its  home  manufacture  is  not  recommended,  and 
is  now  but  rarely  practiced.  The  market  price  of  arsenate  of 
lead  has  varied  widely,  owing  to  strong  competition,  but  usually 
sells  at  from  8  to  10  cents  per  pound  in  100-pound  kegs,  and  at 
20  cents  for  single-pound  packages. 

Arsenate  of  lead  is  now  made  in  a  powdered  form  for  dusting 
on  crops  where  spraying  is  impracticable  or  unsatisfactory.  Most 
of  that  manufactured  in  powdered  form  is  crystalline  and  will 
not  mix  as  readily 'with  water  as  the  paste,  and  is  therefore  not 
recommended  for  use  with  water.  One  manufacturer,  however, 
is  producing  an  amorphous  powder,  which  is  bolted  like  flour,  and 
which  mixes  readily  with  water,  and  may  be  used  exactly  the 
same  as  the  paste,  of  course  using  approximately  only  half  as  much 
weight  for  the  same  effectiveness,  as  half  of  the  paste  is  water. 

4.  Arsenite  of  lead  is  a  compound  very  similar  to  the  arsenate, 
which  is  made  from  sodium  arsenite,  but  it  contains  less  arsenic 
and  usually  much  more  soluble  arsenic,  for  which  reason  its  use 
has  not  proven  satisfactory,  and  is  rarely  sold  by  reliable  dealers. 

Used  in  Water. — The  above  arsenicals  are  generally  diluted 
with  water  and  applied  as  a  spray,  which  is  visually  much  the 
most  efficient  method.  Where  Bordeaux  mixture  or  lime- 
sulfur  is  to  be  sprayed  on  fruit  trees  or  garden  crops  for  the 
control  of  fungous  diseases,  the  arsenical  may  be  added  to  them 
at  the  same  rate  as  to  water.  The  combination  of  arsenicals 
with  other  common  fungicides  is  not  usually  possible  without 
danger  of  serious  injury  to  the  foliage. 

Used  as  Dust. — Under  some  circumstances  the  arsenicals  are 
more  readily  applied  in  the  dust  form.     Dusting  may  l^e  done 


INSECTICIDES  45 

most  effectively  by  the  use  of  a  powder-gun,  which  consists 
of  a  rotating  fan  which  drives  the  poison  from  a  reservoir  through 
a  tube  by  which  it  may  be  directed  to  the  desired  point.  The 
powder-guns  most  commonly  used  are  carried  by  a  man,  though 
larger  machines  carried  on  a  wagon  are  in  use  for  orchard  work. 
Paris  green  is  usually  diluted  with  10  to  20  parts  of  flour,  ground 
gypsum,  or  preferably  air-slaked  lime,  though  some  prefer  to 
use  it  undiluted  when  machines  are  used  which  control  the  amount 
of  the  application.  Dusting  should  be  done  while  the  dew  is 
on  the  foliage  in  early  morning,  except  on  such  plants  as  have  a 
rough  or  adhesive  foliage.  Paris  green  is  frequently  used  as  a 
dust  upon  potatoes,  cabbage  and  other  garden  crops,  as  well  as 
for  dusting  weeds  and  grass  for  grasshoppers,  army  worms,  etc. 
Powdered  arsenate  of  lead  has  recently  been  shown  to  be  an 
effective  remedy  for  the  cotton  boll  weevil  (see  page  272),  and 
is  used  pure.  Its  use  in  dry  form  will  doubtless  be  found  more 
practicable  on  other  crops  than  has  that  of  Paris  green. 

5.  Arsenite  of  lime  is  a  home-made  arsenical,  very  much  cheaper 
than  those  previously  mentioned,  and  giving  very  satisfactory 
results  for  certain  purposes.  It  is  not  as  adhesive  as  arsenate 
of  lead,  and  as  it  sometimes  burns  foliage  has  been  largely  dis- 
carded for  orchard  spraying.  It  is,  however,  very  satisfactory 
for  potatoes  and  other  low-growing  crops,  especially  when  added 
to  Bordeaux  mixture,  which  sticks  it  to  the  foliage,  and  it  may  be 
used  to  good  advantage  for  fighting  grasshoppers  and  leaf-eating 
caterpillars  when  it  is  desired  to  poison  considerable  areas  of 
weeds  or  waste  grass.  The  so-called  Kedzie  formula  is  the  most 
satisfactory,  as  the  soda  hastens  the  complete  combination  of 
the  arsenic,  and  the  resulting  solution  is  in  a  clear  liquid  form 
which  can  be  readily  measured.*     Take  1  pound  of  white  arsenic 

*  Arsenite  of  lime  is  often  made  by  boiling  1  pound  of  lime  with  2  pounds 
of  white  arsenic  in  1  gallon  of  water  for  thirty  to  forty-five  minutes.  This 
results  in  a  paste  of  arsenite  of  lime,  which  settles  in  the  solution.  One  quart 
of  this  mixture  is  used  per  barrel  of  water  or  Bordeaux  mixture,  but  unless 
the  stock  solution  is  always  stirred  equally  well,  the  amount  of  poison  in  a 
quart  will  be  quite  variable,  with  varying  effectiveness;  hence  the  clear 
solution  of  arsenite  of  soda  as  in  the  above  formula  is  preferable. 


46        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

and  4  pounds  of  crystal  salsoda  (2  pounds  only  of  anhydrous  sal- 
soda  are  necessary) ,  and  boil  together  in  1  gallon  of  water  for 
twenty  minutes.  This  forms  a  stock  solution  of  arsenite  of  soda, 
whichmay be  kept  until  needed.  Put  it  in  a  jug  and  label  "  Poison." 
When  ready  to  spray  add  a  quart  of  this  solution  and  3  or  4  pounds 
of  freshly  slaked  lime  to  each  barrel  of  water  (50  gallons) .  When 
used  at  this  rate  the  arsenite  of  lime  will  cost  about  7  cents  for  a 
barrel,  exclusive  of  lalDor  in  its  preparation,  as  compared  with  10 
cents  for  an  equal  amount  of  Paris  green  (J  lb.),  or  20  cents  for 
arsenite  of  lead  (2  lbs.).  Unless  large  quantities  are  to  be  used 
for  the  purposes  indicated,  it  will  hardly  pay  the  small  user  to 
bother  with  its  manufacture,  and  the  danger  of  poisoning  in  the 
mixing  or  in  the  careless  disposal  of  waste  or  uncleaned  utensils 
must  also  be  considered,  though  it  may  sometimes  be  useful  in  an 
emergency  when  manufactured  arsenicals  are  not  available. 

6.  Resifi-soap  Sticker. — Upon  the  smooth  foliage  of  such  plants 
as  cabbage  and  asparagus  it  is  exceedingly  difficult  to  stick 
Paris  green  or  even  arsenate  of  lead  when  used  as  a  spray.  To 
obviate  this  the  addition  of  resin-soap  acts  as  a  sticker.  Place 
5  pounds  of  pulverized  resin  and  1  pint  of  fish-oil  or  any  cheap 
animal  oil,  except  tallow,  in  an  iron  kettle  with  1  gallon  of  water, 
and  heat  until  the  resin  is  softened;  add  the  lye  solution  as  made 
for  hard  soap;  stir  thoroughly;  add  enough  water  to  make  5 
gallons  and  boil  about  two  hours,  or  until  the  mixture  will  unite 
with  cold  water,  making  a  clear,  amber-colored  liquid.  If  the 
mixture  has  boiled  away  too  much,  add  sufficient  water  to  make 
5  gallons.  This  makes  a  stock  solution  of  liquid  resin  soap. 
For  use  add  three  gallons  to  50  gallons  of  water,  and  add  3  gal- 
lons of  milk-of-lime  or  whitewash  (3  lbs.  stone  lime  in  3  gallons), 
and  ^  pound  of  Paris  green.  The  addition  of  lime  turns  the 
small  soap  particles  into  hard  soap  to  which  the  Paris  green 
adheres  and  is  thus  distributed  throughout  the  mixture  in 
uniform  quantity  and  rendered  exceedingly  adhesive.  The 
stock  solution  may  be  added  directly  to  Bordeaux  mixture  with- 
out the  addition  of  extra  lime,  to  which  Paris  green  or  arsenate 
of  lead  may  be  added  in  the  usual  quantity.     Similar  resin  soap, 


INSECTICIDES  47 

called  sticker,  is  sold  by  James  Good  of  Philadelphia,  Pa.,  and  may 
be  used  in  the  same  way  at  the  rate  of  3  pounds  to  50  gallons. 

7.  Poisoned  Bran  Mash. — For  combating  grasshoppers  and  cut- 
worms arsenic  is  often  applied  in  the  form  of  a  bran  mash.  Mix 
1  pound  of  Paris  green  or  London  purple  (or  white  arsenic  col- 
ored with  a  dye)  with  25  pounds  of  bran  or  middlings.  Stir  a 
quart  or  two  of  cheap  molasses  into  a  gallon  of  water  and  moisten 
the  bran,  stirring  thoroughly,  until  it  makes  a  stiff  mash.  Do 
not  add  so  much  water  that  the  mash  will  be  thin  and  will  cake 
when  exposed.  Apply  a  heaping  tablespoonful  near  each  plant 
or  every  2  or  3  feet  in  the  row.  Keep  poultry  out  of  fields 
thus  treated.  For  cutworms  apply  a  day  or  two  before  setting 
plants  and  as  near  evening    as  possible. 

8.  Hellebore. — The  powdered  roots  of  the  white  hellebore  are 
often  used  as  an  insecticide  in  place  of  arsenicals,  especially  for 
currant  worms,  rose  slugs,  and  similar  saw-fly  larvae  and  for  insects 
affecting  crops  soon  to  be  eaten,  as  the  hellebore  is  much  less 
poison  to  man  and  animals  than  arsenicals.  It  may  be  applied 
dry,  diluted  with  from  5  to  10  parts  of  flour,  or  as  a  spray,  1  ounce 
to  a  gallon  of  water.  It  is  too  expensive  to  use  except  for  a  few 
plants  in  the  yard  or  garden,  and  like  pyrethrum,  deteriorates 
with  age  and  if  exposed  to  the  air. 

Harmlessness  of  Arsenicals  when  Properly  Applied. — The  ques- 
tion is  frequently  asked  whether  it  is  safe  to  apply  arsenicals  to 
vegetables  and  fruits  to  be  used  as  food.  Where  sprayed  or  dusted 
as  directed  the  amount  of  arsenic  wdiich  would  be  deposited  on 
the  plant  would  not  be  sufficient  to  cause  any  injury,  and  Professor 
C.  P.  Gillette  has  shown  that  twenty-eight  cabbages  dusted  in  the 
ordinary  way  would  have  to  be  eaten  at  one  meal  in  order  to  pro- 
duce poisonous  effects.  Occasionally  growers  dust  cabbage  with  an 
unreasonable  amount  of  poison,  and  very  rarely  instances  of  poison- 
ing are  recorded,  but  there  is  no  value  in  applying  any  more  poison 
than  is  necessary  to  make  a  thin  film  over  the  surface,  and  more 
than  that  is  wasted.  Because  a  certain  amount  of  poison  will  kill 
an  insect  does  not  indicate  that  a  larger  amount  can  kill  it  any 
"  deader."     Experiments  have  also  shown  that  tobacco  sprayed  as 


48        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

recommended  cannot  possibly  bear  enough  arsenic  to  be  injurious, 
and  that  cattle  or  horses  may  be  pastured  under  trees  sprayed 
with  arsenicals  with  impunity.* 

2.  Contact  Insecticides 

Contact  insecticides  are  used  against  insects  with  sucking 
mouth-parts  and  soft-bodied  biting  insects,  which  may  be  more 
readily  destroyed  by  this  means  than  by  arsenicals.  These  sub- 
stances arc  fatal  to  the  insect  either  by  clogging  the  spiracles 
or  trachea,  and  thus  causing  suffocation,  or  by  corroding  the 
skin.  It  should  be  remembered  that  the  chitinous  skin  of  most 
insects  is  not  easily  corroded,  and  that  in  most  cases  a  material 
strong  enough  to  penetrate  the  skin  will  also  injure  foliage,  so  that 
only  soft-bodied  insects  can  be  combated  with  corrosive  sub- 
stances upon  foliage. 

In  the  application  of  contact  insecticides  it  is  absolutely  essen- 
tial that  the  spray  come  into  contact  with  the  insect,  as  a  mere  spray- 
ing of  the  foliage  is  of  no  value  whatever. 

1.  Kerosene  emulsion  is  one  of  the  oldest  remedies  for  plant- 
lice,  and  other  sucking  and  soft-bodied  insects,  and  is  often 
resorted  to  because  it  is  readily  made  and  the  materials  are 
always  at  hand. 

Dissolve  h  pound  of  hard  or  whale-oil  soap  (or  1  quart  soft 
soap)  in  1  gallon  of  ])oiling  watei'.  Add  2  gallons  of  kerosene  and 
churn  with  a  force  pump  In'  pumping  back  and  forth  for  five  to 
ten  minutes  until  the  oil  is  thoroughly  emulsified,  forming  a 
creamy  mass  with  no  drops  of  free  oil  visible.  This  stock  solution 
is  now  diluted  so  that  the  resulting  mixture  will  contain  the  de- 
sired per  cent  of  kerosene.  Thus  for  aphides  one  part  of  the  stock 
solution  should  be  diluted  with  from  10  to  15  parts  of  water,  giving 
from  4  to  6  per  cent  of  kerosene  in  the  spray,  while  for  a  winter 
wash  for  San  Jose  scale,  it  should  be  diluted  only  three  or  four 

*  This  is  not  true  of  grass  beneath  trees  which  have  Ijecn  sprayed  with 
a  straight-jet  fire-hose,  as  is  commonly  done  in  Massachusetts  in  the  extensive 
operations  against  the  gypsy  moth,  but  refers  to  spraying  which  has  been 
done  with  an  ordinary  spray  nozzle,  which  ajoplies  the  material  as  a  fine  spray. 


INSECTICIDES  49 

times,  giving  from  IG  to  22  per  cent  kerosene.  The  emulsion  must 
l)e  thoroughly  churned  and  should  be  applied  with  a  nozzle  throw- 
ing a  fine  spray.  Apply  only  enough  to  wet  the  insects.  Equally 
effective  emulsions  may  be  made  from  crude  petroleum,  the  pro- 
portion of  the  soap  and  crude  oil  in  the  stock  emulsion  varying 
with  the  quality  of  the  oil.  Emulsions  made  with  some  of  the 
crude  oils  seem  to  be  much  less  injurious  to  foliage  of  some  plants 
than  when  made  with  kerosene.  Such  an  emulsion  is  made  in 
California  from  distillate  oils  and  is  known  as  distillate  emulsion. 
AVe  have  used  crude  Texas  oils  with  equal  success. 

2.  Kerosene. — Pure  kerosene  should  never  be  used  on  foliage,  for 
though  occasionally  someone  will  report  using  it  successfully 
without  injur}',  in  practically  all  cases  serious  burning  of  the  foliage 
results.  It  was  formerly  recommended  against  the  San  Jose 
scale  on  fruit  trees,  but  such  serious  injury  resulted  that  it  has  been 
almost  entirely  discarded,  though  it  may  be  used  on  apple  and  pear 
trees  if  applied  with  a  nozzle  which  throws  a  fine  spra}',  on  a  bright 
sunny  day,  and  only  a  very  thin  film  applied  to  the  tree  while  it  is 
dormant,  but  even  these  trees  are  often  injured  if  the  application 
is  not  made  with  the  greatest  care. 

3.  Crude  Petroleum. — Crude  petroleum  is  used  in  the  same  man- 
ner as  kerosene  against  scale  insects,  but  seems  to  be  less  injurious 
to  the  tree,  and  has  been  extensively  used  in  New  Jersey  against 
the  scale  on  peaches,  where  but  little  injury  has  resulted  where  it 
has  been  carefully  applied.  It  contains  more  heavy  oils  and  con- 
sequently does  not  penetrate  the  bark  so  readily,  and  the  light  oils 
evaporating  leave  the  heavy  oils  on  the  bark  for  some  months, 
which  aid  in  preventing  young  scales  from  getting  a  foothold. 
Crude  oil  for  use  as  an  insecticide  should  have  a  specific  gravity  of 
from  43°  to  45°  Beaume  scale,  and  is  sold  by  certain  Eastern  com- 
panies as  "  insecticide  oil." 

4.  Oil  and  Water  Treatment. — Spray  pumps  have  been  sold  for 
several  years  which  make  a  mechanical  mixture  of  oil  and  water 
in  desired  proportions.  These  have  been  thoroughly  tested  both 
by  entomologists  and  by  extensive  use  by  practical  fruit-growers 
and  the  general  verdict  is  that  they  are  unreliable  and  unsatisfac- 


50        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

tory.  None  of  them  now  on  the  market  give  a  uniform  percentage 
of  oil,  and  injury  to  foliage  is  therefore  liable  to  result.  With  the 
advent  of  miscible  oils  the  oil-and-water  pump  is  not  to  be  recom- 
mended. 

5.  Miscible  Oils.  During  the  last  few  years  several  manufac- 
turers have  placed  on  the  market  under  various  trade  names  what 
are  now  called  miscible  oils.  These  are  petroleum  rendered  solu- 
ble by  the  addition  of  vegetable  oils,  cut  or  saponified  with  an 
alkali,  and  are  really  a  sort  of  liquid  petroleum  soap  which  will 
combine  readily  with  water.  They  have  been  used  principally 
as  winter  washes  against  the  San  Jose  scale,  for  which  they  are 
most  effective  when  diluted  10  or  12  times.  For  a  summer  wash 
they  have  been  used  effectively  against  plant-lice  and  other  insects 
for  which  kerosene  emulsion  would  be  used,  diluted  25  to  30  times. 
In  barrel  lots  the  miscible  oils  sell  at  40  to  50  cents  per  gallon,  thus 
making  the  cost  of  a  gallon  of  mixture  for  a  winter  application  at 
10  per  cent,  4  or  5  cents  per  gallon. 

6.  Whale-oil  and  Other  Soaps. — Any  good  soap  is  an  effective 
insecticide  for  destroying  aphides  and  young  or  soft-bodied  larva?. 
Any  good  laundry  soap  made  into  a  thick  solution  one-half  pound 
per  gallon  is  an  excellent  remedy  for  such  insects  on  house- 
plants.  Whale-oil  or  fish-oil  soap  has  been  extensively  used 
against  scale  insects  and  plant-lice.  The  best  brands  are  made 
from  caustic  potash  rather  than  caustic  soda,  and  should  contain 
not  over  30  per  cent  of  water,  there  being  wide  variation  in  the 
water  content.  For  the  pea  aphis  and  other  aphides  1  pound 
to  6  gallons  of  water  has  been  found  very  effective.  For  a  win- 
ter wash  for  the  San  Jose  scale  2  pounds  per  gallon  of  water  are 
applied  while  hot,  the  soap  being  dissolved  in  hot  water.  The 
soap  can  be  bought  for  3J  to  4  cents  a  pound  in  large  quantities, 
thus  making  the  treatment  for  scale  cost  from  7  to  8  cents  a 
gallon. 

7.  Lime-sulfur  Wash. — The  lime-siilfur  wash  has  always  been 
the  standard  remedy  for  the  San  Jose  scale  on  the  Pacific  Coast, 
and  during  the  last  few  years  has  come  into  wide  use  in  the  East 
for  the  same  pest.     It  has  also  been  found  to  be  an  efficient 


INSECTICIDES  51 

remedy  for  the  pear  leaf  blister-mite,  and  the  oyster-shell 
bark-louse.  In  addition  to  its  insecticidal  properties  it  is  an 
excellent  fungicide,  and  the  spring  applications  just  before  the 
buds  start  are  very  effective  in  killing  out  the  wintering  spores 
of  various  fungous  diseases,  while  the  diluted  wash  is  being  used  as 
a  summer  spray  for  fungous  diseases  in  place  of  Bordeaux  mixture. 

The  usual  formula  is,  unslaked  stone  lime,  20  pounds;  flowers 
(or  flour)  of  sulfur,  15  pounds,  water  to  make  50  gallons.  Stir 
up  enough  water  with  the  sulfur  to  make  a  thick  paste.  Slake 
the  lime  in  the  vessel  in  which  it  is  to  be  cooked  with  a  small 
quantity  of  hot  water.  Then  add  the  sulfur  paste  to  the  slaking 
lime.  Add  10  or  15  gallons  of  water  and  boil  for  forty-five  min- 
utes. The  mixture  may  then  be  diluted  to  make  a  barrel  of  45  or 
50  gallons,  straining  it  carefully  into  the  spray  barrel  or  tank.  A 
large  iron  kettle  or  hog-scalder  may  be  used  for  boiling  the  wash, 
or  where  steam  can  be  made  available  a  steam  pipe  may  be 
run  into  several  barrels  and  the  wash  boiled  in  them.  Such 
barrels  may  well  be  placed  upon  a  platform  so  that  the  wash 
may  be  drawn  from  them  directly  into  the  spray-tank.  The 
materials  for  making  the  wash  will  cost  H  to  1^  cents  per  gallon 
and  the  labor  practically  as  much  more.  The  leading  manufac- 
turers and  dealers  in  insecticides  are  now  selling  concentrated 
lime-sulfur  solution  which  is  all  ready  for  use  by  merely  diluting 
to  the  desired  strength,  at  a  rate  which  will  make  the  solution 
to  be  used  cost  from  2^  to  3  cents  per  gallon,  nearly  as  cheap 
as  it  can  be  made  at  home  and  with  the  saving  of  time  and  a  dis- 
agreeable job.  In  many  communities  a  central  plant  makes  the 
wash  and  can  sell  it  with  a  fair  profit  at  a  low  rate. 

8.  Home-made  Concentrated  Lime-sulfur. — During  the  last  few 
seasons  many  large  growers  have  been  making  their  own  con- 
centrated lime-sulfur  solution,  and  where  the  quantity  to  be 
used  warrants,  a  considerable  saving  may  be  effected.  The  New 
York  Agricultural  Experiment  Station  has  made  very  careful 
studies*  of  the  best  methods  of  making  and  diluting  the  mixture 
from  which  the  following  is  quoted: 

*Bulletins  329  and  330,  N.  Y.  (Geneva)  Agricultural  Experiment  Station. 


52        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Geneva  Statiun  Formula  for  Concexthated  Lime-sulfuk  Solution. 

r  Pure  CaO 36  lbs. 

Lime    ]  If  95  per  cent  pure. . ., 38  lbs. 

I  If  90  per  cent  pure 40  lbs. 

Sulfur,  high  grade,  finely  divided 80  lbs. 

Water 50  gals. 


Dilutions  for  Dormant  and  Summer  Spraying  with  Lime-sulfur 

Mixtures 


Reading  on 
hydrometer. 

Amount  of  Dilution.     Number  of  Gallons  of  Water  to  One 
Gallon  of  Lime-sulfur  Solution. 

P"or  San  Jos^  Scale. 

For  Blister -mite. 

For  Summer  Spray- 
ing of  Apples. 

Degrees  Beaumd. 
36 

9 

81 

8i 

■8 

7^ 

7i 

6! 

6i 

6 

51 

5i 

5 

4^ 

4i 

3! 

3i 
3 

2^ 

2i 
2 

12^ 
12 
lU 
11 

lOi 
10 

9^ 

9' 

8* 

8 

7i 

7 

6.V 

6 

5* 

5 

4! 

41 

4 

3| 

3\ 

3 

45 

35 

43  i 

34 

41+ 

33 

40 

32 

37 1 

31 

36i 

30. 

34i 

?9 

32 1 

98 

31 

•^ 

29+ 

'?6 

27 1 

25. 

26 

24 

24i 

23. 

22f 

?? 

211 

21. 

19^ 

20 

18| 

19 

17 

18 

16 

17. 

15 

18 

14 

15       

12| 

"  In  making,  slake  the  lime  in  about  10  gallons  of  hot  water, 
adding  the  lumps  of  lime  gradually  to  avoid  too  violent  boiling  and 
spilling  over.  .  .  .  The  sulfur  must  be  thoroughly  moistened  and 
made  into  an  even,  fluid  paste  without  lumps  (before  adding  to 
the  lime).  .  .  .  Pour  in  the  sulfur  paste  gradually  during  the 
slaking,  stirring  constantly  to  prevent  the  formation  of  lumps, 
and  when  the  slaking  has  finished  add  the  full  amount  of  water 


INSECTICIDES  53 

and  boil  gently  for  one  hour.  If  kettles  and  fire  are  used,  more 
than  the  required  amount  of  water  may  be  used  at  first,  to  com- 
pensate for  evaporation,  or  the  volume  ma}'  be  kept  constant  by 
adding  successive  small  quantities  to  hold  the  mixture  at  the 
original  level,  as  shown  by  a  notch  on  a  stick  resting  on  the  bot- 
tom of  the  kettle,  and  marked  when  the  mixture  first  begins  to 
boil.  When  boiling  with  live  steam  the  mixture  will  be  more 
likely  to  increase  in  volume  than  to  decrease,  so  that  no  water 
need  be  adtled. 

"  This  concentrate  will  keep  with  little  change,  unless  the 
weather  is  below  5°  F.,  if  stored  in  filled,  stoppered  barrels. 
Even  in  open  receptacles  there  will  be  no  loss  if  the  surface  be 
covered  by  a  layer  of  oil  to  prevent  access  of  air.  Each  boiling 
should  be  tested  with  a  Beaume  hydrometer  *  and  its  density 
marked  on  the  barrels  or  other  containers." 

The  dilution  is  based  upon  the  specific  gravity  as  shown  by 
the  hydrometer  and  may  be  safely  made  according  to  the  out- 
line in  the  above  table. 

In  making  this  mixture  it  is  important  that  only  high-grade, 
pure  lime  should  be  used,  and  lime  with  less  than  90  per  cent 
calcium  oxid  (CaO)  should  be  discarded. 

9.  Self-boiled  Lime-sulfur. — Self-boiled  lime-sulfur  has  proven 
to  be  the  only  safe  fungicide  for  the  foliage  diseases  of  the 
peach  and  stone  fruits,  and  is  used  extensively  as  a  summer  spray 
on  j)ome  fruits.  As  a  winter  wash  for  San  Jose  scale  it  has  not 
proven  as  effective  as  the  boiled  mixture,  but  when  used  as  a 
summer  spray  for  fungous  diseases  it  also  has  considerable 
insecticidal  value.  Its  general  usefulness  as  a  summer  insecticide 
is  in  the  process  of  experimental  determination,  l)ut  sufficient 
results  have  already  been  secured  to  warrant  the  statement 
that  it  will  prove  of  considerable  value  as  a  summer  insecticide 
for  certain  pests,  where  it  is  to  be  used  for  the  fungous  diseases 
of  the  host  plant  at  the  same  time.  This  mixture  has  been  developed 

*  These  hydrometers,  made  specially  for  testing  lime-suKur  mixture,  may 
be  obtained  from  the  Bausch  &  Lomb  Optical  Co.,  Rochester,  N.  Y.,  and 
other  dealers  in  laboratory  glassware. 


54        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

chiefly  by  the  work  of  Mr.  W.  M.  Scott  of  the  United  States. 
Department  of  Agriculture,  from  whose  latest  bulletin  *  the 
following  is  quoted : 

"  In  order  to  secure  the  best  action  from  the  lime,  the  mix- 
ture should  be  prepared  in  rather  large  quantities,  at  least  enough 
for  200  gallons  of  spray,  using  32  pounds  of  lime  and  32  pounds 
of  sulfur.  The  lime  should  Ijc  placed  in  a  Ixarrcl  and  enough  water 
(about  6  gallons)  poured  on  to  almost  cover  it.  As  soon  as  the 
lime  begins  to  slake  the  sulfur  should  be  added,  after  first  running 
it  through  a  sieve  to  break  up  the  lumps,  if  any  are  present. 
The  mixture  should  be  constantly  stirred  and  more  water  (3  or 
4  gallons)  added  as  needed  to  form  at  first  a  thick  paste  and  then 
gradually  a  thin  paste.  The  lime  will  supply  enough  heat  to 
boil  the  mixture  several  minutes.  As  soon  as  it  is  well  slaked 
water  should  be  added  to  cool  the  mixture  and  prevent  further 
cooking.  It  is  then  ready  to  be  strained  into  the  spray  tank, 
diluted,  and  applied. 

"  The  stage  at  which  cold  water  should  be  poured  on  to  stop 
the  cooking  varies  with  different  limes.  Some  limes  are  so  sluggish 
in  slaking  that  it  is  difficult  to  obtain  enough  heat  from  them  to 
cook  the  mixture  at  all,  while  other  limes  become  intensely  hot 
on  slaking,  and  care  must  be  taken  not  to  allow  the  boiling  to 
proceed  too  far.  If  the  mixture  is  allowed  to  remain  hot  for 
fifteen  or  twenty  minutes  after  the  slaking  is  completed,  the  sulfur 
gradually  goes  into  solution,  combining  with  the  lime  to  form 
sulfids,  which  are  injurious  to  peach  foliage.  It  is  therefore 
very  important,  especially  with  hot  lime,  to  cool  the  mixture 
quickly  by  adding  a  few  buckets  of  water  as  soon  as  the  lumps 
of  lime  have  slaked  down.  The  intense  heat,  violent  boiling, 
and  constant  stirring  result  in  a  uniform  mixture  of  finely  divided 
sulfur  and  lime,  with  only  a  very  small  percentage  of  the  sulfur 
in  solution.  It  should  be  strained  to  take  oub  the  coarse  particles 
of  lime,  but  the  sulfur  should  be  carefulh'  worked  through  the 
strainer." 

10.  Sulfur. — Pure  sulfur  is  one  of  the  best  remedies  for  red 
*  Farmers'  Bulletin,  440,  U.  S.  Dept.  of  Agr.,  p.  34. 


INSECTICIDES  55 

spider,  on  whatever  plants  it  may  occur,  and  for  other  mites  which 
infest  citrus  fruits.  It  may  be  dusted  on  the  infested  plants  or  trees 
or  applied  with  any  other  insecticide,  using  1  or  2  pounds  to  50 
gallons.  For  citrus-mites  the  lye-sulfur  wash  and  sulfide  of  lime 
are  extensively  used.  Sulfur  is  frequently  dusted  in  poultry 
houses  to  rid  them  of  lice,  and  may  be  mixed  with  lard  and  rubbed 
on  the  skin  of  domestic  animals  affected  with  lice. 

11.  Pyrethrum,  buhach,  or  Persian  insect  powder,  is  made  by 
pulverizing  the  petals  of  the  pyrethrum  blossom,  and  kills  insects 
by  clogging  their  breathing  pores.  It  is  not  poisonous  to  man  or 
domestic  animals  and  may  therefore  be  used  where  other  insecti- 
cides would  be  objectionable.  It  is  chiefly  used  for  household 
pests,  and  in  greenhouses  and  small  gardens.  It  deteriorates 
rapidly  with  age  and  should  be  kept  in  tight  cans.  An  objection 
to  much  commonly  bought  is  that  it  has  been  kept  in  stock  too 
long  b}'  the  retailer,  thus  losing  its  strength.  Large  users  buy 
direct  from  the  only  American  manufacturers,  the  Buhach  Pro- 
ducing Co.,  Stockton,  Cal.  It  may  be  used  as  a  dry  powder, 
pure  or  diluted  with  flour,  or  in  water  at  the  rate  of  1  ounce  to  2 
gallons,  which  should  stand  a  day  before  using.  For  immediate 
use  it  should  be  boiled  in  water  for  five  or  ten  minutes.  It  is  fre- 
quently Ijurnt  in  rooms  to  destroy  mosquitoes  and  flies,  for  which 
it  is  effective,  without  leaving  any  odor  after  the  room  is 
aired.* 

12.  Tobacco. — A  tobacco  decoction  may  be  made  by  boiling  or 
steeping  tobacco  leaves,  stems,  and  refuse  in  water  at  the  rate  of 
1  pound  to  1  or  2  gallons.  This  may  be  diluted  slightly  according 
to  the  strength  of  the  tobacco  and  the  insect  to  be  combated. 
Such  a  decoction  is  an  excellent  remedy  for  dipping  plants  affected 
with  aphides,  and  may  be  used  as  a  spray  for  plant-lice  and  similar 
soft-bodied  insects.  Various  extracts  and  solutions  of  tobacco  are 
now  sold  by  manufacturers  which  are  extensively  used  in  spraying 
against  plant-lice,  and  which  are  proving  more  satisfactory  on 
account  of  their  uniform  strength.  Tobacco  dust  has  been  used 
successfully  against  root-infesting  aphides  by  removing  the  sur- 

*  See  Farmers'  Bulletin,  444,  U.  S.  Dept.  Agr.,  p.  7. 


56        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

face  soil  and  applying  a  liberal  dressing  of  the  tlust  and  then 
covering.  The  rains  leaching  through  the  tobacco  carry  the 
tobacco  water  to  the  affected  roots  and  destroy  or  repel  the 
aphides. 

3.  Repellants 

Repellants  include  any  substance  which  may  be  applied  to  a 
plant  or  animal  to  prevent  insect  attack.  A  popular  notion  that 
any  vile-smelling  substance  will  repel  insect  attack  seems  to  have 
very  little  evidence  in  its  support.  Tobacco  dust,  air-slaked  lime, 
or  even  fine  road  dust,  thoroughly  covering  a  plant  will  prevent 
the  attack  of  various  flea-beetles  and  leaf-eating  beetles,  but  to  be 
successful  the  plants  must  be  frequently  dusted  and  kept  w^ell  cov- 
ered. Bordeaux  mixture,  our  most  widely  used  fungicide,  when 
liberally  sprayed  on  potatoes  and  tomatoes,  acts  as  a  repellant  to 
the  little  black  flea-beetles  which  often  seriously  damage  the 
young  plants. 

The  various  fly-sprays  which  are  used  for  spraying  cattle  to 
prevent  the  annoyance  of  flies  act  merely  as  repellants. 

Fruit-trees  are  often  painted  with  a  thick  soap  solution  con- 
taining 1  pint  of  crude  carbolic  acid  to  10  gallons  as  a  repellant 
for  the  adult  borers  which  lay  their  eggs  on  the  bark. 

A  substance  which  has  come  into  prominence  in  the  fight 
against  the  gypsy  moth  in  New  England  is  tree  tanglefoot,  a  sticky 
substance  the  same  as  is  used  to  coat  fly-papers.  This  comes  in  the 
form  of  a  very  sticky  paste,  a  band  of  which  is  placed  around  the 
trunk  of  the  tree  and  which  prevents  the  ascent  of  caterpillars,  as 
it  will  remain  sticky  for  some  weeks.  It  may  be  used  in  the  same 
way  to  prevent  the  wingless  female  canker  worms  and  other 
wingless  insects  from  ascending  trees,  or  to  prevent  the  ascent  of 
caterpillars  on  unaffected  trees. 

Various  proprietary  insecticides  are  frequently  offered  for  sale 
with  wonderful  claims  for  their  effect  as  repellants,  but  only  in  rare 
cases  are  they  of  any  value  except  for  use  as  a  dust  as  already  sug- 
gested. One  of  the  most  common  fakes  of  this  sort  is  that  of  the 
itinerant  tree-doctor  who  offers  to  bore  a  hole  in  a  tree  and  plug 
it  with  sulfur  or  other  offensive  compounds,  which  will  effectively 


INSECTICIDES  57 

prevent  any  insect  or  fungous  depredations.     A  generous  price 
per  tree  is  charged,  which  is  the  only  "  effect "  of  the  treatment. 

4.  Gases. 

Carbon  Bisuljid  (or  disulfid)  is  extensively  used  against  insects 
affecting  stored  goods  and  grains,  and  for  root-feeding  insects.  It 
is  a  clear,  volatile  liquid  giving  off  fumes  heavier  than  air.  It  is 
sold  in  25-  to  100-pound  cans  at  10  to  12  cents  per  pound.  It  may 
be  thrown  directly  onto  grain  without  injury  to  it  or  placed  in 
shallow  dishes.  For  grain  in  store  in  fairl}-  tight  rooms  apply  5  to 
S  pounds  to  every  100  bushels,  distril)uting  the  bisulfid  over  the 
surface  or  in  pans  containing  not  over  one-half  to  1  pound  each. 
Make  the  enclosure  as  tight  as  possible;  covering  the  grain  with 
l)lankets  or  other  tight  cover,  if  necessary,  and  leave  for  twenty- 
four  hours.  Recent  experiments  have  shown  that  the  vapor  is 
much  less  effective  at  low  temperatures  and  that  the  dosage  must 
be  greatly  increased  at  temperatures  below  60°  F.  For  fumi- 
gating buildings  "  there  should  be  about  1  square  foot  of  evap- 
orating surface  to  every  25  square  feet  of  floor  area,  and  each 
square  foot  of  evaporating  surface  should  receive  from  one-half 
to  1  pound  of  liquid."  For  fumigating  clothing  or  household 
goods,  place  them  in  a  tight  trunk  and  place  an  ounce  of  liquid 
in  a  saucer  just  under  the  cover.  The  gas  is  exceedingly  explosive; 
allow  no  fire  or  light  of  any  kind  around  the  building  or  enclosure 
until  it  has  been  well  aired.  The  fumes  should  not  be  inhaled,  for 
though  not  seriously  poisonous,  they  have  a  suffocating  effect  and 
will  soon  produce  dizziness  and  a  consequent  headache.  The 
treatment  for  root-maggots  and  root-feeding  aphides  is  discussed 
in  connection  with  those  insects  (pages  355  and  496).* 

Hydrocyanic  Acid  Gas  is  extensively  used  for  the  fumigation 
of  nursery  trees  and  plants,  certain  greenhouse  insects,  pests  of 
dwelling  houses,  storehouses,  mills,  etc.,  and  in  California  for 
scale  insects  on  fruit  trees.     It  is  made  by  combining  cyanide  of 

*  For  a  complete  discussion  of  the  use  of  this  gas,  see  Farmers'  Bulletin, 
145,  U.  S.  Dept.  Agr.,  and  see  page  197  below. 

Carbon  tetrachloride  is  now  used  for  some  purposes  in  much  the  same 
manner  as  carbon  bisulphide,  and  is  not  so  explosive. 


58        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

potassium,  sulfuric  acid  and  water.  The  gas  is  slightly  lighter 
than  air  and  is  a  most  deadly  poison.  Its  use  is  to  be  recom- 
mended only  by  thoroughly  competent  and  careful  persons  who  are 
fully  advised  as  to  the  method  of  use  for  the  particular  purpose 
desired.  Concerning  its  use  advice  should  be  sought  from  the  State 
Agricultural  Experiment  Station,  or  from  the  State  Entomologist, 
or  from  the  Bureau  of  Entomology  of  the  U.S.  Department  of  Agri- 
culture. The  general  methods  used  arc  fully  described  by  the  late 
Professor  W.  G.  Johnson  in  his  l)ook  ''  Fumigation  Methods  \ 
(Orange  Judd  Co.),  with  which  should  be  considered  the  results 
of  more  recent  experiments  and  experience. 

Sulfur  Dioxid. — The  fumes  of  burning  sulfur,  mostly  sulfur 
dioxid,  have  long  been  recognized  as  a  standard  remedy  for  the 
fumigation  of  dwellings  and  barracks  for  insect  pests.  Successful 
fumigation  for  the  l^edl^ug  has  been  reported  when  stick  sulfur  has 
been  burned  at  the  rate  of  2  pounds  per  1000  cubic  feet  of  space. 
The  chief  objection  is  the  strong  bleaching  effect  of  the  fumes  in 
presence  of  moisture  and  their  destructive  action  on  vegetation. 
Recently  this  gas  has  been  extensively  used  under  the  name  of 
''  Clayton  gas,"  for  the  fumigation  of  ships  and  ships'  cargoes,  par- 
ticularly grain.  It  is  forced  into  the  tight  hold  of  a  ship  by  specia-l 
apparatus  and  is  exceedingly  penetrating  and  effective.  The 
germinating  power  of  seeds  is  quickly  destroyed,  but  they  are  not 
injured  for  food.  1  to  5  per  cent  of  the  gas,  with  an  exposure  of 
twenty-four  hours,  is  effective  for  most  seed  and  grain  pests.  It 
cannot  be  used  on  vegetation  or  for  moist  fruits. 

Tobacco  Fumes. — Tobacco  is  extensively  used  as  a  fumigant 
for  aphides  in  greenhouses  and  for  certain  plants,  such  as  melons, 
by  using  it  under  covers.  Several  forms  are  now  commonly 
used.  Tobacco  or  nicotine  extracts  are  sold  under  various  trade 
names,  which  are  volatilized  by  heating  either  with  a  small  lamp 
or  by  dropping  hot  irons  into  the  dishes  containing  the  fluid. 
The  same  material  nisij  be  purchased  in  the  form  of  paper  w^hich 
has  been  saturated  with  the  extract  and  which  is  burned  accord- 
ing to  directions,  a  certain  amount  being  sufficient  for  so  many 
cubic  feet  of  space,  which  forms  a  more  convenient  method  of 


INSECTICIDES  59 

application.  Certain  finuly  ground  tobacco  jjowders,  called 
"  fum'gating-kind  "  tobacco  powder,  are  used  in  the  same  way 
and  are  much  the  cheapest  form  of  tobacco  for  fumigation, 
though  requiring  slightly  more  work  in  preparing  for  fumigation. 
These  tobacco  preparations  are  excellent  for  the  fumigation  of 
household  plants,  which  may  be  placed  in  a  closet  and  then 
fumigated  according  to  the  directions  of  the  particular  brand 
employed.  Melon  vines,  young  apple  trees,  bush  fruits,  and 
similar  outdoor  crops  may  be  effectively  rid  of  plant-lice  by 
fumigating  with  tobacco-paper  under  a  frame  covered  with 
canvas  or  muslin  sized  with  glue  or  linseed  oil. 

For  further  discussion  of  Insecticides   see  Farmers'    Bulletin  127,  U.  S. 
Qepartment  of  Agriculture- 


CHAPTER  VI 
SPRAYING  AND  DUSTING  APPARATUS 

Atomizers. — Hand  atomizers  of  the  general  style  shown  in 
Fig.  26  may  be  purchased  at  any  hardware  store,  and  are  useful 
for  applying  soap  or  oil  solutions  to  a  few  house  or  garden  plants. 
They  are  not  adapted  for  more  extensive  use  and  to  try  to  spray 
many  plants,  or  a  tree,  with  them,  is  a  waste  of  time. 

Bucket  Pumps. — The  simplest  type  of  spray  pump  is  that 
made  to  use  in  a  bucket.  The  better  types  usually  cost  $5  to 
$8,  the  cheaper  styles,  selling  for  $2  or  $3,  being  inferior  and 
unsatisfactory. 


Fig.  26. — An  atomizer  handy  for  spraying  a  few  plants. 

There  is  as  much  difference  in  the  structure  of  bucket  pumps 
as  in  those  of  the  barrel  type,  and  many  of  the  statements  made 
below  concerning  the  latter  v.dll  apply  also  to  bucket  pumps. 
The  Ijuckct  pump  should  have  an  air  chamber,  so  that  a  steady 
pressure  may  l)e  maintained.  Some  firms  are  making  bucket 
pumps  of  the  same  general  type  of  the  barrel  pump  shown  in  Fig. 
34,  which  are  very  satisfactory  in  this  regard.  A  footrest  attached 
to  the  pump  and  a  clamp  to  attach  the  pump  to  the  bucket  are 
useful  accessories, 

60 


SPRAYING  AND  DUSTING  APPARATUS 


61 


Many  firms  arc  now  selling  these  pumps  mounted  in  largo 
galvanizcd-iron  covered  buckets,  and  furnished  with  a  mechanical 
agitator.  This  is  a  tlesirable  arrangement,  for  the  buckets  are 
much  larger  than  those  ordinarily  used,  thus  saving  frequent 
filling,  while  the  cover  prevents  slopping,  and  the  pump  is  always 
ready  for  use  without  the  necessity  of  hunting  up  a  bucket  and 
then  cleaning  it,  which  is  necessary  after  using  a  bucket  which 
is  used  for  other  purposes. 

Bucket  pumps  are  useful  for  small  gardens  or  for  a  few  small 
trees,  or  bushes. 


Fig.  27. — a,  a  cheap  type  of  bucket  pump  with  no  uir-chamber,  which 
will  not  maintain  satisfactory  pressure;  b,  a  better  type  of  bucket 
pump  with  small  air-chamber.     (Courtesy  Deming  Co.) 

Knapsack  Pumps. — The  kiiapsack  pump  consists  of  a  copper 
or  galvanized-iron  tank  carried  on  the  back  like  a  knapsack,  in 
which  is  mounted  a  bucket  pump  with  a  lever  handle  for  pumping. 
In  the  better  makes  this  handle  is  detachable,  and  a  plain  handle 
may  be  attached  so  that  the  tank  may  be  used  as  a  simple  bucket 
pump,  for  which  a  footrest  is  attached  to  the  tank.  The  pump 
should  have  a  good  mechanical  agitator.  The  copper  tanks 
are  preferable,  for  Bordeaux  mixture  will  soon  eat  through  gal- 
vanized iron.     Knapsack  pumps   are  useful  for  spraying  such 


62        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


crops  as  tomatoes,  melons,  etc.,  which  cover  the  ground,  so  that 

it  is  difficult  to  drive  through  them  without  injuring  the  vines, 

crops  growing  on  steep  hillsides,  or  for  a  small  acreage  of  any 

garden  crops,  small  fruits,  or  small 

trees.      The    main     objections     to  1^*-^  "^^ 

them  are  that  they  are    heavy  to 

carry,  thus  limiting  their  use  to  a 

small    area;     they    frequently   slop 

over,  and  wet  the   carrier's    back; 

and    the    pumps    do    not    develop 

sufficient  pressure  for    some  kinds 

of    work.     Consequently    they  are 

not  as  much  used  as  formerly,  but 

are    useful    for   the   purposes   indi- 


FiG.  28. — Bucket  pump  mounted  in 
bucket,  and  mounted  in  tank  v.ith 
agitator.     (Covu-tesy  Deming  C'o.) 


Fig.  29. — Bucket     pump     with 
large  air-chamber,  which  will 
maintain  a  good  pressure. 
(Courtesy  F.  E.  Myers  &  Bro.) 


cated,  and  inasmuch  as  they  may  also  be  used  as  a  simple 
bucket  pump,  they  are  to  be  preferred  to  them.  The  cost  varies 
from  $8  to  $12  or  $15. 

Compressed-air  Sprayers. — In  recent  j'ears  the  compressed- 
air  sprayer  has  come  into  favor  for  use  in  small  gardens.  It 
consists  of  a  brass  tank  which  is  filled  with  the  liquid;   the  air 


SPRAYING  AND  DUSTING  APPARATUS 


63 


is  compressed  by  an  air-pump,  and  spraying  continues  until 
the  pressure  runs  down,  when 
a  stopcock  is  turned  and  the 
pressure  is  again  raised  by  pump- 
ing. The  tank  holds  from 
3  to  5  gallons,  and  is  carried 
beneath  one  arm,  slung  Ijy  a 
strap  over  the  other  shouldei'. 
The  chief  ol)jections  to  this  type 
are  that  it  is  not  ver}'  con- 
venient to  fill,  though  the  newer 
models  are  much  improved,  is 
not  readily  repaired,  has  no 
agitator,  and  recjuires  frequent 
pumping.  On  the  other  hand, 
they   are  easily  carried,  do    not 

leak,  and  leave  both  hands  free,   ^'f "  ^O.-One  of  the  best  types  of 

knapsack    sprayers.      Note    foot- 
so    that   one    might  be  used    for       rest,    agitator,  handle,    and   wide 

spraying  a  small  tree  from  a  step-      "^"'^P'-    (Deming  Co.) 
ladder.     These    compressed-air    sprayers    cost    from    $5    to   $8. 

Barrel  Pumps. — 
The  most  serviceable 
spray  pump  for  the 
average  farm  is  the 
barrel  pump.  With  a 
good  barrel  pump  100 
to  150  full-grown 
apple  trees  may  be 
sprayed  in  a  day,  so 
that  it  will  be  found 
sufficient  for  an  or- 
chard of  500  trees  or 
less.  By  using  a  row- 
spraying  attachment, 
a  few  acres  of  pota- 


FiG.  31.— The  knapsack  sprayer  in  use. 
(Spramotor  Co.) 


64        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


toes  or  other  row  crops  may  be  sprayed  with  a  Inirrel  pump  much 
more  quickly  than  by  hand.  In  buying  a  row  attachment,  be  sure 
that  it  is  adjustable  for  rows  of  different  widths.  A  good  barrel 
pump  costs  from  $15  to  $25.  Most  of  the  pumps  sold  'at  $10 
or  less  are  too  light  to  do  effective  work  or  are  not  well  constructed. 
Numerous  pump  companies  advertise  in  the  agricultural  papers, 
and  after  considering  the  following  points  one  may  select  a 
suitalile  pump  from  their  catalogs: 


Fig. 32.-t'ojn])iesyed-  New  type  of  compressed-air  sprayer  with 

air    sprayer    with  separate  pump.     (E.  C.  Brown  Co.) 

section  of  tank 
removed  to  show 
air  pump  within. 

1.  The  pump  should  ])c  guaranteed  to  furnish  four  nozzles 
at  SO  to  100  pounds'  pi'cssure  wnth  ordinary  pumping. 

2.  It  should  have  a  large  air  chamber  within  the  barrel,  and 
not  projecting  above  it. 

3.  As  few  of  the  working  parts  of  the  pump  as  possible  should 
be  above  the  head  of  the  barrel,  as  exposed  parts  are.  easily 
broken. 

4.  The  cylinder,  plunger,  valves  and  working  parts  should  be  of 
brass.  The  handles  and  other  parts  commonly  made  of  cast  iron 
are  much  more  durable  when  made  of  malleable  or  galvanized  iron. 


SPRAYING    AND  DUSTING   APPARATUS 


65 


5.  Tlierc  should  bo  a  good  incchanical  agitator  of  the  paddle 
type,  preferably  arranged  so  that  it  can  be  worked  with  the 
pump  handle  without  operating  the  pump.  An  agitator  is 
essential  to  keeping  the  mixture  in  suspension.  Agitators  of  the 
so-called  "  jet-type,"  in  which  a  stream  from  the  bottom  of  the 


Fig.  33. — An  undesirable  type  of 
barrel  sprayer — now  off  the 
market;  the  air-chamber  and 
other  parts  above  the  barrel 
render  it  top-heavy,  and  may 
be  easily  broken. 


Fig.  34. — A  desirable  type  of  barrel 
pump  embodying  most  of  the 
features  described.  (Morrill  & 
Morley.) 


cylinder  is  supposed  to  agitate  the  liquid,  are  unsatisfactory 
and  allow  a  loss  of  pressure  without  sufficiently  agitating  the 
liquid. 

6.  The  pump  should  be  so  attached  to  the  barrel  that  it  can 
be  quickly  removed  for  repairs.  Those  pumps  which  have  lugs 
for  attaching  the  pump  plate  to  the  barrel  are  much  better  than 
.those  with  screws. 


G6        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.   35. — Two  types  of    double-acting     lever    punipa,   to   be  mounted   on 
truck  and  connected  with  tank. 


Fig.  36 — Double-acting  horizontal  pump  mounted  on  250-gallon  tank. 
A  good  type  of  outfit  for  medium  sized  commercial  orchards.  (Va. 
Agr.  Exp.  Sta.) 


SPRAYING  AND   DUSTING  APPARATUS 


G7 


8.  The  valves,  with  their  seats  or  cages,  should  be  readily 
removable  for  cleaning,  and  should  be  so  constructed  that  they 
remain   evenly  ground. 

All  of  these  points  may  not  be  embodied  in  any  one  pump, 
but  most  of  the  better  pump  manufacturers  are  embodying  these 
features  in  their  newer  models,  a  good  exampl*^  of  which  is  shown 
in  Fig.  34. 

Barrel,  knapsack,  and 
bucket  pumps  are  manufac- 
tured which  have  separate 
tanks  for  oil  and  water 
which  are  mixed  in  a  de- 
sired proportion  and  sprayed 
as  a  mechanical  mixture. 
They  have  been  found  un- 
reliable in  controlling  the 
amount  of  oil,  and  are  not 
now  in  general  use. 

Horizontal  Pumps. — For 
larger  orchards  and  shade 
trees,  the  double-acting 
horizontal  pumps  which  are 
operated  with  a  lever,  as 
shown  in  Fig.  35,  furnish 
more  power  and  conse- 
cjuently  make  more  rapid 
work  possible.  They  are 
mounted  on  100-  or  150- 
gallon  tanks  and  may  be 
arranged  for  filling  the  tank  where  running  water  is  not  available. 
These  pumps  cost  from  $30  to  $50  and  will  maintain  100  to  125 
pounds  pressure  with  four  to  eight  nozzles.  They  are  usually 
used  with  two  men  spraying  and  another  driving  and  pumping, 
or  a  fourth  man  pumps  and  changes  places  now  and  then  with 
the  driver,  as  the  operation  of  this  type  is  rather  too  heavy  for 
one  man  constantly. 


Fig.  37. -Gasoline  power  sprayer,  complete. 
Note  wide  tread  steel  wheels,  steel  tower 
on  tank,  and  intake  hose  for  filling  tank 
where  running  water  is  not  available ;  3  J 
h.p.,  4-cycle  gasoline  engine,  will  main- 
tain 10  nozzles  at  200  lbs.  pressure. 


68  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  38. — One  of  the    latest    three-cylinder    power    pumps,    designed  for 
spraying  shade-trees  and  woodlands. 


FiGo  39. — Row-spraying  attachment  for  use  with  barrel  pump,  adjustable 
for  various  width  of  rows.     (Darning  Co.) 


1 


SPRAYING  AND  DUSTING  APPARATUS 


69 


Power  Outfits. — For  orchards  of  much  over  500  trees  or  for 
extensive  shade-tree  work  a  gasoline  power  outfit  is  more  econom- 
ical and  enables  a  large  area  to  be  covered  more  quickly,  which  is 
often  a  most  important  consideration.  Most  of  the  pump  manu- 
facturers and  many  gas  engine  companies  are  selling  such  outfits 
mounted  upon  a  truck,  with  spray  tank,  and  tower  complete  for 
from  $250  to  $400. 

Traction  Sprayers. — For  a  small  acreage  of  potatoes  or  other 


Fig.  40. — A  good  type  of  geared  sprayer  for  row  crops. 

row  crops,  a  barrel  pump  with  row  attachment  is  very  satisfac- 
tor}',  but  for  any  considerable  acreage,  a  two-wheeled  traction 
sprayer  is  much  more  economical  of  labor  and  time  which  are 
the  two  chief  items  in  the  cost  of  spraying.  Such  traction 
spraj^ers  are  made  of  widely  different  types,  the  power  in  all 
cases  being  furnished  by  a  gear  or  chain  which  operates  the  pump 
from  the  wheels.  The  mechanical  construction  of  the  traction 
sprayers  should  be  carefully  studied,  and  if  possible  tested,  before 


70         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

purchasing,  as  they  differ  greatly  in  efficiency.  The  better  types 
cost  from  $60  to  $100,  and  usually  have  attachments  adapting 
them  fcr  all  sorts  of  row  crops,  such  as  potatoes,  strawberries, 
bush  fruits,  grapes,  etc.,  which  require  different  styles  of  piping 
to  properly  direct  the  nozzles. 

Several  traction  sprayers  are  sold  for  orchard  work  but,  though 
they  arc  fairly  satisfactory  for  small  trees,  they  do  not  develop 
enough  power  for  spraying  large  trees,  and  have  a  heav}^  draft. 

Gas  '<prayers. — A  very  handy  and  efficient  spraying  outfit  is  now 


Fig.  41. — Row    sprayer  applying  arsenate    of    lead  to    potatoes,    showing 
arrangement  of  nozzles  to  cover  vines.     (After  Britton.) 

made  which  uses  carbonic-acid  gas  as  the  power  (Fig.  42).  The 
liquid  is  placed  in  a  steel-tank,  to  which  is  attached  a  tube  of 
carbonic-acid  gas,  the  same  as  is  used  for  soda  fountains.  The 
gas  is  admitted  to  the  tank  by  a  valve  until  the  desired  pres- 
sure is  secured,  and  the  gas  then  forces  the  liquid  out,  thus 
obviating  the  need  of  a  pump.  The  outfit  is  mounted  on  a 
steel  truck  with  steel  tower,  or  may  be  mounted  on  any  wagon, 
and  is  also  mounted  on  two  wheels  with  suitable  attachments 
for  row  spraying.  The  cost  of  the  gas  is  somewhat  higher 
than     gasoline    or     hand     power,    but  less    labor    is    required 


SPRAYING  AND  DUSTING  APPARATUS 


71 


and  constant  high  pressure  is  maintained.  Unfortunateh'  the 
gas  makes  a  chemical  combination  with  hmc-sulfur  mixture,  so 
that  this  type  of  sprayer  is  not  adapted  for  its  use.  A  modifi- 
cation of  the  gas  sprayer  outfit  has  recently  been  made  in  which 
a  gasoline  engine  operates  an  air-compressor,  which  places  an  air 
pressure  on  the  liquid  in  the  tank  in  the  same  manner  as  would 
the  compressed  carbonic-acid  gas.  It  is  claimed  that  these 
outfits  are  superior  to  an  ordinary  gasoline  engine  and  pump, 
in  that  the  liquid  does  not  pass  through  the  pump,  and  that 


Fig.  42. — Carbonic-acid  gas  sprayer  at  work. 

there  is  therefore  less  wear  on  the  pump,  and   that  the  outfit  is 
lighter. 

A  somewhat  similar  use  of  compressed  air  is  being  made  for 
orchard  sprayers  by  a  few  large  fruit  growers.  The  outfit 
consists  of  two  steel  tanks  holding  50  to  100  gallons  each, 
which  are  fitted  with  valves  connecting  them  and  at  the  outlet. 
One  of  these  tanks  is  filled  with  liquid  and  in  it  is  an  agitator 
operated  from  the  wheel.  The  other  tank  is  charged  with  com- 
pressed air  by  an  air-compressor  stationed  at  the  filling-station. 
The  air-pressure  secured  in  the  air-tank  is  sufficient  to  force  all 


72         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

of  the  liquid  out  of  the  other  tank  at  a  pressure  never  below  100 
pounds,  and  averaging  125  to  150  pounds.  The  advantages  of 
these  outfits  are  that  they  are  much  lighter,  so  that  more  liquid 
can  be  carried,  and  that  the  men  on  the  outfit  need  have  no 
mechanical  ability,  as  is  necessary  with  the  operation  ofa  gasoline 
engine  pump.  The  trucks  and  tanks  are  much  cheaper  than  the 
gasoline  sprayers,  but  the  cost  of  the  engine  and  air-compressor 
at  the  charging  station  makes  the  total  cost  probably  more.  It 
is  also  necessary  for  each  tank  to  return  to  the  charging  station, 
and  it  is  not  possible  to  use  a  supply  tank,  as  is  commonly  done 
with  gasoline  sprayers.  However,  these  outfits  are  in  successful 
operation  by  some  of  the  largest  orchardists,  who  believe  them  to 


Fig.  43. — Vermorel,  bordeaux,  and  disk  type  of  nozzles.  . 

be  much  the  best  type  of  sprayers  for  large  operations,  so  that  they 
merit  study  bj'  those  contemplating  extensive  spraying. 

Nozzles. — A  good  nozzle  is  as  essential  as  a  good  pump  for  suc- 
cessful spraying.  The  best  nozzles  now  in  common  use  are  of 
three  types. 

The  Vermorel  type  consists  of  a  small  chamber  into  which  the 
liquid  is  admitted  at  a  tangent  and  leaves  through  a  small  hole  in  a 
removable  cap,  thus  making  a  fine,  cone-shaped  spray.  A  small 
pin,  with  a  spring  to  hold  it  back  when  not  in  use,  serves  as  a  dis- 
gorger  to  remove  any  sediment  which  may  clog  the  outlet.  This 
type  of  nozzle  is  made  in  many  slightly  different  styles  and  often 
sold  under  trade  names,  such  as  the  Demorel,  Mistry  and  others. 
A  slightly  modified  form  has  no  spring  attached  to  the  disgorger, 
but  has  a  loose  cap  which  is  held  away  from  the  pin  by  the  force  of 


SPRAYING  AND  DUSTING  APPARATUS 


73 


the  liquid,  and  the  outlet  is  disgorged  by  simply  pressing  the  cap 
down  on  the  pin.  Such  are  the  Spramotor  (Spramotor  Mfg.  Co.) 
and  Vapor-Mist  Nozzles  (Field  Force  Pump  Co.)  and  are  disgorged 
rather  more  easily  than  those  with  springs.  The  Vermorel  type 
makes  the  finest  spray  of  the  three  types  of  nozzles  and  will  there- 
fore be  preferred  for  use  with  oils  and  fungicides  where  a  very  fine 
spray  is  desired.     The  liquid  must  be  thoroughly  strained,  for  they 

are  easily  clogged.  Usually  two  or 
three  nozzles  are  attached  to  a  Y,  T,  or 
ring,  for  orchard  or  shade  tree  work. 

Disk  Type. — An  evolution  from  the 
latter  type  has  recently  been  brought 
out  in  which  the  chamber  has  been 
made  much  broader  and  flatter,  thus 
giving  a  very  strong  rotary  motion  to 


Fig.  4-1. — A  cluster  of  spramotor  noz- 
zles and  single  nozzle  of  the  same 
type. 


Fig.  45. — Angle  form  of 
disk  type  nozzle,  partic- 
ularly useful  for  orchard 
spraying.       (Friend    Mfg. 

Co.) 


theliciuid  and  breaking  it  into  a  fine  spray  through  a  large  aperture, 
so  that  no  disgorger  is  required.  This  is  known  as  the  disk  type  of 
nozzle,  and  was  originated  by  the  Friend  Mfg.  Co.,  but  is  now  sold 
b}-  all  the  leading  pump  companies  in  various  forms  under  different 
trade  names.  The  nozzle  is  light,  does  not  catch  on  twigs,  and  the 
large  aperture  prevents  clogging,  even  of  unstrained  liquid,  and 
allows  the  passage  of  a  large  amount  of  liquid,  one  of  these 
nozzles  spraying  as  much  as  two  or  three  Vermorels.  This  type 
was   designed   for  use  with  j)ower  sprayers,  but  will   give  good 


74         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


results  with  barrel  or  horizontal  pumps  which  will  maintain  a 
pressure  of  85  pounds  or  more.     One  of  these  nozzles  to  each  line 

of  hose  will  be  sufficient  with  a  barrel 
pump,  and  two  to  a  line  with  power. 
The  disk  type  is  adapted  to  orchard 
and  shade-tree  work. 

The  Bordeaux  nozzle  is  of  entirely 
different  structure,  the  spray  being 
formed  by  a  straight  stream  hitting  a 
lip  which  breaks  it  into  a  fan-shaped 
spray,  the  fineness  of  the  spray  being 
governed  by  the  width  of  the  aperture. 
To  unclog  the  nozzle  the  core  through 
which  the  stream  emerges  is  reversed, 
thus  giving  a  straight  stream  and  clear- 
ing the  nozzle  immediately.  For  this 
reason  the  Bordeaux  nozzle  is  partic- 
ularly adapted  to  traction  sprayers 
where  several  nozzles  are  used  and  it  is 
necessary  to  unclog  them  quickly.  It 
is  usually  preferred  for  garden  and  row 
crops,  and  some  prefer  it  for  tree  work, 
though  it  is  not  as  widely  used  for  that 
purpose  as  the  previous  types. 

At  the  present  time  these  three 
types  of  nozzles  are  much  superior  to 
all  others,  and  the  user  will  do  well  to 
stick  to  them  and  let  others  experiment 
with  new  or  cheap  creations  until 
they  have  proven  themselves  better. 
Nozzles  which  merely  sprinkle  or  make  a 
strong  long  stream  are  undesirable  for 
spraying. 

Extension  Rods. — In  orchard  spraying  an  extension  rod  is  a 
necessity.  Most  pump  companies  sell  a  bamboo  rod  enclosing  a 
light  brass  tube,  and  fitted  with  thread  for  the  nozzle  at  the  tip  and 


Fig.  46. — Bamboo  extension 
rod  at  left,  and  iron  rod 
with  drip-guard  at  right. 


SPRAYING  AND  DUSTING  APPARATUS 


75 


45-degree  elbow 
for  attaching 
nozzles  to  end 
of  rod  for 
orchard  spray- 
ing. 


with  a  shut-off  or  stopcock  at  the  lower  end,  so  that  the  stream 

ma}'  be  cut  off  when  moving  from  tree  to  tree  and  the  pressure 

maintained.     These  are  light  and  easily  handled,  but  the  bamboo 

and  connections  frequently  break,  so  that  many 

prefer  using  a  straight  piece  of  three-eighths   or 

one-half  inch  galvanized-iron  pipe,  threaded  for 

the  nozzle  and  stopcock.     Wooden  handle-grips, 

or  grips  made  of  burlap,  ma}'  be  wired  around  the 

pipe,  so  that  it  will  be  easier  to  hold.     Ten  feet 

is  a  good  length. 

The  nozzle  should  be    attached  to  the  rod 
by  a  45-degree  connection,  so  that  it  points  at 
that  angle.     This  enables  one  to  spray  directly  over  the  topmost 
branches  and  under  the  lower  ones,  making  the  work  much  easier 

and  more  effective  than 
where  the  nozzle  is  attached 
straight. 

In  spraying  low-grow- 
ing crops,  such  as  melons, 
beans,  etc.,  upon  which  it 
is  desirable  to  spray  the 
under  surface  of  the  foliage, 
a  short  pipe  about  3  feet 
long  is  usually  used,  with 
the  nozzle  attached  to  it 
by  an  L,  so  that  the  noz- 
zle is  at  right  angles  to 
the  pipe  and  will  spray  the 
under  surface. 

Hose. — Use  the  best 
four-ply  one-half-inch  hose 
for  barrel  or  power  sprayers  and  three-eighths-inch  for  bucket  or 
knapsack  sprayers.  For  barrel  or  power  sprayers  use  couplings 
with  double-length  shanks  which  will  permit  the  use  of  two  clamps 
or  bands  on  either  side  of  the  union.  "Wire  bands  for  attaching 
hose  to  pump  or  nozzle  are  unsatisfactory  and  should  be  avoided. 


Fig.  46. — Spraying  squash  with  underspray 
nozzle  at  right  angle  to  rod. 


Fig.  47. — The  old  way:  attempting  to  spray  tall  apple-trees  from  the  ground 
and  making  very  hard  work  of  it. 


Fig.   48. — The  modem  way;    spraying    apple-trees    from  a  rough   tower 
bolted  to  a  one-horse  wagon. 


SPRAYING  AND  DUSTING  APPARATUS 


77 


Strainers. — To  obviate  the  delay  cau.sccl  by  nozzles  clogging 
with  dirt  and  sediment,  strain  all  mixtures  through  a  fine  copper 
strainer  when  filling  the  spray  tank.  Have  the  tank  tight  and 
see  that  it  is  clean  before  filling. 

Towers. — For  orchard  spra3'ing  it  is  essential  that  the  operator 
be  high  enough  to  spra}'  all  parts  of  the  tree  quickly  and  thor- 
oughly. Most  of  the  power  outfits  are  built  with  a  tower  such 
as  shown  in  Fig.  37.  A  very  serviceable  tower  may  be  erected  on 
a  one-  or  two-horse  wagon,  at  slight  expense.  It  is  bolted  to  the 
body,  so  that  it  is  easily  removed.     The  floor  should  be  as  high 


Fig.  49. — A  powder-gun    for    applying    insecticides    in    dust  form.     (After 

Weed.) 


as  the  weight  of  the  wagon  and  roughness  of  the  land  will  allow, 
and  the  railing  should  be  about  the  height  of  the  sprayer's  w^aist. 
Dusting  Apparatus. — For  dusting  a  few  plants  a  small  powder 
bellows  may  be  used,  but  where  crops  are  to  be  dusted  a  powder 
gun  will  be  found  much  more  economical.  One  of  the  best 
types  is  shown  in  Fig.  49.  This  has  tubes  which  will  direct 
the  dust  onto  two  rows  if  desired  and  regulates  the  amount 
of  dust  used.  Larger  traction  outfits  mounted  on  tw^o  wheels 
are  made  for  dusting  row  crops,  but  hand  work  with  the  smaller 
machine  has  usually  proven  more  effective.  Larger  outfits  are 
also  made  for  carrying  in  a  wagon  for  dusting  orchards.  These 
have  been  used  extensively  in  the  Ozark  region,  but  the  use  of 
dust  has  not  proven  as  effective  for  most  purposes  as  the  spray, 
though  it  is  superior  for  some  purposes,  as   for   the  cotton  boll 


78        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

weevil  (see  p.  272),  and  may  sometimes  be  used  where  it  is  dif- 
ficult to  secure  or  haul  water. 

Other  mechanical  device  j  for  combating  particular  insects 
will  be  described  in  connection  with  them.* 

*  For  further  information  see  "  Information  Concerning  Spraying  for 
Orchard  Insects,"  A.  L.  Quaintance,  Yearbook,  U  S.  Dept.  Agr.,  for  1908, 
p.  267. 


CHAPTER   VII 

Insects  Affecting  Grains,  Grasses,  Forage  and  Miscellaneous 

Crops 

Several  of  our  worst  insect  pests  live  normally  in  grass  land, 
but  when  they  become  numerous  feed  upon  grains  and  various 
forage  and  garden  crops,  so  that  they  are  not  readily  classed  as 
enemies  of  any  one  crop,  and  will  therefore  be  discussed  together. 

White  Grubs  * 

Among  the  most  common  pests  of  corn,  strawberry  beds, 
and  garden  crops  are  the  large  white  grubs  which  feed  upon 
the  roots  and  often  kill  the  plants.  Their  habit  of  lying  curled 
up  in  a  semicircle,  and  the  large  brown  head,  white  body,  and 
enlarged  abdomen,  at  once  distinguish  them  from  other  forms 
of  grubs.  Although  they  are  very  similar  in  color  and  form, 
there  are  numerous  species,  all  of  which  are  the  young  of  different 
species  of  the  large  brown  May-beetles  or  June-bugs,  as  they  are 
commonly  called,  which  frequently  fly  into  lights  in  late  spring. 

Life  History. — The  eggs  are  laid  mostly  in  June,  preferably 
in  grass  land,  but  also  in  corn  fields  and  gardens.  The  egg  is 
of  a  broad  oval  shape,  pure  white,  about  one-tenth  inch  long, 
and  is  laid  in  a  small  ball  of  earth  a  half  inch  in  diameter,  from 
1  to  5  inches  below  the  surface.  The  eggs  hatch  in  about  two 
weeks,  most  of  them  hatching  by  the  middle  of  July.  The 
young  grubs  feed  upon  plant  roots,  and  grow  slowly,  as  it 
requires  two  years  or  more  for  them  to  become  full-grown. 
In  the  fall  they  burrow  down  in  the  soil,  gradually  going  deeper 

*  Lachnosterna  spp.  Family — ScarahceidoB .  See  S.  A-  Forbes,  Bulletin 
116,  Illinois  Agricultural  Experiment  Station. 

79 


80 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


as  frost  approaches  until  by  the  first  freeze  most  of  them  are 
from  7  to  14  inches  deep.  The  next  year  they  do  much  more 
serious  damage,  and  land  which  has  been  in  sod  and  then 
planted  in  corn,  strawberries,  or  other  crops  of  which  they  are 
fond,  is  often  so  full  of  the  grubs  that  the  crops  are  ruined.  In 
1895  an  Illinois  field  of  250  acres  which  had  been  in  grass  for 
twenty  years  was  so  injured  that  the  sod  could  be  rolled  up 
like  a  carpet  over  the  entire  field.  It  is  not  surprising,  therefore, 
that  Professor  Forbes  records  finding  as  many  as  thirty-four  grubs 
to  the  hill  of  corn  in  another  Illinois  field  which  had  previously 
been    in  sod.     Where  sod  is  taken  into  greenhouses  the  grubs 


Fig.  50. — Lachnostema  arcuata:  a,  beetle;  b,  pupa;  c,  egg;  d,  newly-hatched 
larva;  e,  mature  larva;  /,  anal  segment  of  same  from  below,  a,  b, 
e,    enlarged    one-fourth;     c,    d,  f,    more    enlarged.     (After   Chittenden, 

U.  S.  Dept.  Agr.) 

often  become  serious  pests.  When  the  grub  is  two,  or  possibly 
sometimes  three  years  old,  it  forms  a  small  oval  cell  from  3  to 
10  inches  below  the  surface  and  there  changes  to  a  soft,  white 
pupa,  sometime  in  June  or  July.  The  pupal  stage  lasts  slightly 
over  three  weeks,  and  in  August  or  September  the  adult  beetle 
wriggles  out  of  the  pupal  skin,  but  remains  in  the  pupal  cell 
until  the  following  spring,  when  it  comes  forth  fully  hardened. 
Thus  three  full  years  are  occupied  by  the  life-cj'cle  of  each  brood, 
though  grulDS  in  all  stages  of  development  may  be  found  in  the 
soil  every  year. 

The  adult  l^eotles  feed  at  night  upon  the  foliage  of  various 
trees.     They  hide  in  the  soil  during  the  day,  migrate  to  the  trees 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE  81 

u  ■ 

at  dusk,  and  return  to  the  fields  just  before  daybreak.  The 
different  species  have  favorite  food  plants,  but  all  of  our  common 
deciduous  shade  and  forest  trees  are  more  or  less  eaten,  poplar, 
willow,  and  maple  being  particularly  relished.  On  a  warm  evening 
the  beetles  may  often  b3  heard  feeding  and  their  work  may  be 
identified  by  the  ragging  of  the  foliage,  as  if  it  had  been  torn. 

Control. — As  allowing  land  to  remain  in  grass  for  several  years 
is  conducive  to  the  increase  of  the  grubs,  a  frequent  rotation  will 
prevent  their  mviltiplication,  the  grass  being  followed  by  potatoes, 
buckwheat,  small  grains,  or  some  crop  not  seriously  injured  by 
them. 

As  the  beetles  remain  in  the  pupal  cells  over  winter  and  are 
tender  and  not  fully  hardened,  deep  plowing  and  thorough  har- 
rowing in  fall  or  early  spring  will  kill  large  numbers  of  them 
by  breaking  open  the  cells  and  exposing  them  to  the  weather 
and  by  burying  and  crushing  them. 

Swine  will  gorge  themselves  on  grubs  in  badly  infested  land, 
and  if  confined  so  that  they  will  thoroughly  root  it  over,  will 
very  effectually  rid  it  of  them.  Flocks  of  chickens  or  turkeys 
following  the  plow  will  catch  a  considerable  number  of  grubs, 
as  do  the  crows  and  blackbirds,  which  pay  for  the  corn  they  eat 
by  the  war  they  wage  on  grubs.     •  '- 

The  beetles  may  be  jarred  from  the  trees  upon  which  they  are 
feeding  in  the  cooler  part  of  the  night  and  collected,  as  is  exten- 
sively done  in  Europe.  Lanterns  hung  over  pans  or  tubs  contain- 
ing water  with  a  surface  film  of  kerosene  placed  near  the  trees  on 
which  they  feed,  will  catch  large  numbers  on  warm  nights  when 
they  are  flying. 

Wireworms* 

Wireworms  are  hard,  shining,  slender,  cylindrical,  brown 
larva?  about  three-quarters  to  1  inch  long,  which  bore  into 
the  seed  of  corn,  wheat  and  other  grains,  often  necessitating 
replanting,  and  also  feed  on  their  roots,  as  well  as  on  potatoes, 
turnips,  and  many  garden  crops.      They  are  the  young  stage  of 

*  Family  Elateridce. 


82         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


w 


brownish    beetles    of   the    family    Elateridce,    which   from    their 

habit  of  snapping  their 
bodies    up   in   the   air 
are   known   as   "  click 
beetles."     The    beetles 
are  one-half    to   three- 
quarters  inch  long,   de- 
cidedly flattened,  dark 
brown,    often  with 
darker  markings,  with 
short  heads,  and  shield- 
shaped     thoraxes,     as 
shown  in  Fig.    50.     Although  the 
common  wireworms   look  much 
alike,    examination    usually    re- 
veals that  they  belong  to  several 
species    which  are  distinguished 
by  a  comparison  of  the    caudal 
segments,  as  shown  in  Fig.  51. 

Life  History. — The  life  history 
is  very  similar  to  that  of  the 
white  grubs,  except  that  from 
three  to  five  years  are  required 
for  the  complete  life  cycle.  The 
eggs  are  deposited  in  old  sod 
land,  which  is  the  favorite 
breeding  ground.  The  detailed 
life  histories  have  not  been  care- 
fully studied,  but  the  second  year 
after  grass  land  has  been  planted 

in  grain   is    that    in   which    the 
YiG   50  — A ,  beetle  of  wheat  wireworm  ,      .    .  , . 

(Agriotes  mancus)Xi;B,D,  beetle  ^'orst     mjury     occurs,     particu- 

(X4)  and  wireworm  (X7)  oi  Draste-  larly  with    corn,  upon   which  the 

rn^elegans;  .J' ^^^  ^°"\f  ^TAftTr  attack  is  more  concentrated  than 

(Melanotuscribulosus)  X4^.     (Atter 

Forbes.)  with    small   grains.      The   larvae 

become  full  grown  in  midsummer,  form  small  cells  in  the  soil 


C 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE 


83 


and  in  them  transform  to  pupie.  Three  or  four  weeks  later 
the  adult  beetles  shed  the  pupal  skins,  but  few  of  them  make 
their  way  to  the  surface  during  the  fall,  most  of  them  remaining 
in  the  pupal  cells  until  the  following  spring. 

Control. — As  the}'  resemble  the  white  grubs  in  life-cycle,  so 
the  means  of  control  are  similar.  By  plowing  in  late  summer 
or  early  fall  and  thoroughly  harrowing  for  a  month  or  so,  large 
numbers  of  the  pupae  and  newly  transformed  beetles  will  be 
destroyed.  When  the  wireworms  are  numerous  in  restricted 
areas,  as  they  often  are  on  spots  of  low  moist  land,  they  may  be 
effectually  trapped  with  but  little  labor  by  placing  under  boards 
bunches  of  clover  poisoned  with    Paris  green.      A  short  rotation 


Fig.  51. — A,  last  segment  of  Melanotus  communis,  dorsal  view '  (After 
Forbes);  5,  the  wheat  wireworm,  Agriotes  mancus^a,  b,  c,  d,  details 
of  mouth-parts,  enlarged;  C,  caudal  segment  of  the  wireworm  of  Draste- 
terius  elegans;  D,  caudal  segment  of  the  wireworm  of  Asaphes  decoloratus, 
much  enlarged.     (A,  C,  Z>,  after  Forbes;  fi,  after  Slingerland.)- - 


of  crops  in  which  land  is  not  allowed  to  remain  in  grass  for  any 
length  of  time  will  prevent  their  increase.  Many  remedies  have 
been  suggested  for  these  pests,  but  few  of  them  have  proved 
to  have  much  merit  in  careful  tests.  Coating  the  seed  with  gas 
tar,  as  is  done  to  protect  it  from  crows,  has  been  very  widely 
practiced,  and  though  previous  experiments  indicated  that  it  could 
not  be  relied  upon,  Dr.  H.  T.  Fernald  conducted  tests  in  Massa- 
chusetts in  1908  and  1909  in  which  seed  coated  wath  •  gas-tar 
and  then  dusted  in  a  bucket  of  fine  dust  and  Paris  green  suffi- 
cient to  give  the  corn  a  greenish  color,  was  effectively  protected, 
the  treatment  seeming  to  act  as  a  repellant,  and  not  affecting 
the  germination  of  the  seed. 


84         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Cutworms* 

Under  the  general  term  cutworms  we  commonly  designate 
any  of  the  larva  of  several  species  of  moths,  which  are  more 
or  less  similar  in  general  appearance  and  hal^its,  and  which  have 
the  habit  of  feeding  on  low-growing  vegetation,  and  cutting  off 
the  stem  just  at  the  surface  of  the  ground.  They  should  be 
carefully  distinguished  from  white  grubs,  which  are  sometimes 


Fig.  52. — Earth  removed  from  base  of  seedling  to  show  cutworm  in  hiding — 

natural  size. 

wrongly  called  cutworms  on  account  of  their  similar  habits. 
Some  of  the  species  attack  certain  crops  more  commonly  than 
others,  Init  most  of  them  arc  quite  omnivoi'ous  in  their  feeding. 
When  they  become  overabundant  th('>'  w\\\  cat  an}'thing  green 
and  succulent — foliage,  flowers,  butls,  fruit,  stalks,  or  roots,  and 
sometimes  migrate  to  other  fields  in  armies  like  the  army  worms. 
Some  species  commonly  climl)  young  fruit  trees  which  have  been 

*  "\'arious  species  of  the  family  Noctuidce. 


INSECTS  AFFECTING  GRAINS,   GRASSES,  FORAGE  85 

planted  on  grassy  land  or  which  are  allowed  to  grow  in  grass 


Fig.    53. — Greasy    cutworm     (Agrotis  Fig.    54. — The    dark-sided  cut- 

ypsilon);    o,  larva;   6,  head  of  same;  worm       (Agrotis       messoria). 

c.     adult  —  natural     size.        (After  (After  Riley.) 
Howard,  U.  S.  Dept.  Agr.) 


Fig.  55. — Pen'dromia  saucia:  a.  adult,  b.  c,  d,  full-grown  larva\-  e,  f,  eggs 
all  natural  size  except  e,  which  is  greatly  enlarged.  (After  Howard, 
U.  S.  Dept.  Agr.) 

or  weeds,  and  are  known  as  climbing  cutworms.     Our  common 
species  are  most  injurious  to  garden  crops  and  to  corn,  cotton, 


86         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

tobacco  and  similar  crops  grown  in  hills  or  rows,  small  grains 
and  forage  crops  being  injured  but  rarely. 

Though  over  a  score  of  species  are  common,  it  is  not  practica- 
ble to  distinguish  them  in  this  discussion,  and  though  their  life 
histories  are  somewhat  different,  they  may  be  considered  as  a  class. 

The  adults  are  moths  with  dark  fore  wings,  variously  marked 
with  darker  or  lighter  spots  and  narrow  bands  as  shown  in 
Figs.  52-59,  and  with  lighter  hind-wings,  which  are  folded  over 
the  back  when  at  rest.  Like  the  cutworms,  they  feed  at  night, 
sipping  the  nectar  from  flowers,  and  are  known  as  owlet 
moths.  The  females  deposit  their  eggs  in  grass  land  or  where 
a  crop  has  been  allowed  to  grow  up  in  grass  and  weeds  in  late 


Fig.  56. — The  bronzed  cutworm  (Nephelodes  minians  Guen.) :    back  and  side 
views  of  larva — enlarged,  and  moth — natural  size.     (After  Forbes.) 

summer,  laying  them  in  patches  on  the  stems  or  leaves  of  grasses 
or  weeds,  or  on  stones  or  twigs  in  such  places. 

The  little  caterpillars  which  hatch  from  these  eggs  in  August 
and  September  feed  on  the  roots  of  whatever  vegetation  is  available 
until  frost,  going  deeper  as  it  approaches,  and  finally  hollow  out 
small  cells,  in  which  they  curl  up  and  hibernate  until  the  next 
spring.  The  next  spring  they  are  exceedingly  hungry  after  their 
long  fast,  and  attack  any  vegetaton  at  hand  with  surprising  vorac- 
ity. If  the  land  is  in  grass  or  weeds  they  have  plenty  of  food, 
and  if  it  is  then  plowed  and  planted  in  some  crop,  it  will 
certainly  be  injured. 

The  cutworms  usually  become  full  grown  during  late  spring 
or  early  summer,  and  are  then  about  1^  to  2  inches  long,  of 
a  dull  l)rown,  gray  or  blackish  color,   often  tinged   with  green- 


INSECTS  AFFECTING   GRAINS,    GRASSES,   FORAGE         87 

ish,  and  more  or  less  marked  with  longitudinal  stripes,  oblique 
dots  antl  dashes,  the  markings  usually  being  of  a  subdued 
tone,  so  that  the  cutworm  harmonizes  in  color  with  the 
soil.  They  are  cylindrical,  with  the  head  and  prothoracic  plate 
horny  and  reddish  brown,   and  bear  three  pairs  of  jointed  leo-s 


Fig.  57. — Cutworm  moths:  b,  the  well-marked  cutworm-moth  {Noctva 
clandestina  Harris);  the  dingy  cutworm  {Feltia  subgothica  Haworth); 
male  (w)  and  female  (/)  moths.     (After  Slingerland.) 

on  the  thorax  and  five  pairs  of  prolegs  on  the  abdomen.  The 
mature  caterpillars  pupate  in  cells  a  few  inches  below  the  sur- 
face and  in  three  or  four  weeks  the  adult  moths  emerge,  usually 
in  July  and  early  August  in  the  Central  and  Northern  States 
and  earlier  farther  south. 

Thus  there  is  usually  but  one  generation  a  year  in  the  Xorth 
while  in  the  South  there  are  commonly  two  generations  and  in 
some  cases  three.  Though  other  stages  than  the  larvte  of 
various  species  are  known  to  sometimes  hibernate,  nevertheless 


88         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


the  worst  injury  is  usually  done  in  the  ;  pring,  when  young  plants 
have  just  been  set  or  are  just  appearing. 

Control. — It  is  evident  from  their  life  history  that  like  the 
white  grubs  and  wireworms,  cutworms  may  be  most  effectually 
combated  by  plowing  in  late  fall  and  again  plowing  and  har- 
rowing thoroughly  in  early  spring,  so  as  to  keep  the  land  fallow 
and  thus  starve  them  out.  Land  which  is  to  be  planted  in 
corn  or  crops  subject  to  cutworm  injury  should  be  plowed  as 
early  as  possible  in  late  summer  of  the  preceding  year  and  kept 
fallow  so  that  the  moths  will  not  deposit  their  eggs  upon  it, 
as  they  will  if  it  is  left  in  grass  or  weeds. 


Fig.  58. — Moth  of  the  glassy  cut-      Fig.  5!).  —  Granulated   cut-worm  {Agrotis  an- 
worm    {Hadena    devastatrix  nexa).  a,  larva;  /,  pupa;  h.  adult — natural 

Brace).     (After  Forbes.)  size.     (After  Howard,  U.  S.  Dept.  Agr.) 

Poisoned  bran  mash  (see  p.  47)  is  proljaljly  the  best  thing 
for  destroying  cutworms,  and  if  well  applied  a  few  days  before 
plants  are  set  or  a  few  days  after  seed  is  planted,  will  often 
protect  crops  on  infested  land.  On  corn  land  it  may  be  applied 
with  a  seed  drill,  and  in  gardens  an  onion  drill  is  sometimes 
used  in  the  same  way,  placing  the  mash  on  the  sui'face  near 
the  plants;  or  it  may  be  applied  by  hand,  placing  a  tablespoonful 
near  each  plant  or  every  2  or  3  feet  in  the  row.  Distribute 
the  mash  late  in  the  afternoon,  so  that  it  will  still  be  moist 
when  the  worms  feed  at  dusk.  Keep  poultry  away  from  fields 
so  treated.  Clover  which  has  been  thoroughly  sprayed  or  clipped 
in  water  containing  one-third  pound  Paris  green  per  barrel  may  be 
used  in  the  same  way,  particularly  along  the  outside  of  fields  to  be 
protected  from  invasion  or  along  borders  of  fields  next  to  grass. 


INSECTS  AFFECTING   GRAINS,   GRASSES,   FORAGE        89 

Market  gardeners  frequent!}'  protect  cabbage,  tomato  and 
similar  plants  by  knocking  the  bottoms  out  of  tin  cans  or  making 
cylinders  of  building  paper  and  placing  these  around  the  stems, 
sinking  them  into  the  soil.  Where  cutworms  assume  the  climbing 
habit  and  attack  fruit  trees,  distribute  the  bran  mash  or  poisoned 
clover  liberally  around  the  bases  of  the  trees  and  put  a  band 
of  tanglefoot  around  the  trunk  of  each  tree,  which  will  prevent 
their  ascent.  Thorough  cultivation  of  the  orchard  and  neighbor- 
ing land  will  also  reduce  their  numbers.  When  they  assume  the 
migratory  habits  of  army  worms,  they  may  be  controlled  by  the 
same  methods  as  described  for  them.  Garden  plants  may  some- 
times he  protected  from  cutworms,  as  well  as  flea  beetles,  by  dip- 
ping them  in  arsenate  of  lead,  3  pounds  per  barrel,  when  planting. 

The  Chinch-bug  * 

The  adult  Chinch-bug  is  al)out  one-fifth  inch  long,  with  a 
black  body.  Its  white  wings  lie  folded  over  each  other  on  the 
abdomen,  and  arc  marked  l)y  a  small  black  triangle  on  their 
outer  margins,  while  the  bases  of  the  antennae  and  the  legs  are 
red.  The  young  bugs  are  yellowish  or  bright  red  marked  with 
l)rownish-l3lack,  l^ecoming  darker  as  they  grow  older.  Along 
the  Atlantic  coast  and  along  the  southern  shores  of  the  Great 
Lakes  north  of  a  line  from  Pittsburg,  Pa.,  to  Toledo,  Ohio,  the 
majority  of  the  adults  have  short  wings  reaching  but  half  over  the 
abdomen  and  are  incapable  of  flight;  but  between  the  Alleghany 
and  Rocky  Mountains  the  long- winged  form  greatly  predominates. 
It  occurs  also  in  restricted  localities  in  Central  America  and 
along  the  Pacific  coast.  The  worst  injury  is  to  small  grains 
and  corn  in  the  Central  and  North  Central  States,  but  frequently 
injury  is  done  in  the  Eastern  States,  especially  to  timothy  meadows 
which  have  stood  for  several  years.  Though  individually  insig- 
nificant, when  assembled  in  countless  myriads  chinch-bugs  have 
doubtless  been  of  greater  injury  to  tlie  farmers  of  the  Mississippi 
Valle}'  than  any  other  insect  attacking  grain  crops,  the  total 
damage  from  1850  to  1909  being  estimated  at  $350,000,000.t 

*  Blissus  leucopierus  Say.     Family  Lygoeidoe. 

t  See  Circular  113,  Bureau  Entomology,  U.  S.  Dept.  Agr.,  F.  M.  Webster. 


90         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Life  History. — During  the  winter  the  bugs  hibernate  in  clumps 
of  grass,  in  the  butts,  and  in  old  shocks  of  corn,  or  under  what- 
ever rubbish  is  available.  In  early  spring  they  assemble  in 
fields  of  grass  and  small  grains.  Soon  they  pair  and  the  females 
commence  to  lay  their  small  yellowish-white  eggs  upon  the 
roots  or  bases  of  the  stalks,  each  laying  some  150  to  200  eggs. 

The  eggs  are  laid  from  the  middle  of  April  until  the  first  of 
June,  depending  upon  the  latitude  and  weather,  and  hatch  in 
two  or  three  weeks.  As  the  nymphs  grow  they  often  do  serious 
injury  to  small  grains  and  grass,  upon  which  they  become  full 
grown  about  the  time  of  harvest.  When  wheat  is  harvested 
they  spread  to  oats  and  soon  to  corn,  but,  curiously  enough,  though 


P'lG.  60. — The  chinch-bug  {Blissus  leucopterus  Say):  adult  at  left;  a,  b,  eggs 
magnified  and  natural  size;  c,  young  nymph;  e,  second  stage  of  nymph; 
/,  third  stage ;  <;,  full-grown  nymph  or  pupa ;  d,  h,  i,\egs;  i,  beak  through 
which  the  bug  sucks  its  food.     (After  Riley.) 

the  adults  have  wings  they  travel  from  field  to  field  on  foot,  were  it 
not  for  which  fact  we  should  be  at  a  loss  to  cope  with  their  migra- 
tion. Eggs  are  now  laid  upon  the  unfolding  leaves  of  the  corn, 
from  which  the  nymphs  commence  to  emerge  in  about  ten  days. 
This  second  brood  matures  on  corn  in  August  and  September  and 
is  the  one  which  later  hibernates  over  winter,  though  where  corn 
is  not  available  the  whole  season  may  be  passed  on  grass. 

Control. — The  burning  over  of  grass  land,  and  the  grass  along 
fences,  hedges,  and  roads,  as  soon  as  it  becomes  dry  enough  in 
late  fall  and  early  winter,  is  of  prime  importance  to  destroy 
the  bugs  after  they  have  gone  into  hibernation.     The  removal 


INSECTS  AFFECTING   GRAINS,  GRASSES,   FORAGE         91 

of  all  corn  stalks  from  the  fields  and  plowing  the  butts  under 
deeply,  or  where  th€  bugs  are  very  abundant,  raking  out  the 
butts  and  burning  them,  will  rid  the  fields  of  the  pest. 

It  is  practically  impossible  to  combat  the  pest  in  the  summer 


Fig.  61. — Corn-plant  two  feet  tall  infested  with  chinch-bugs.     (After  Webster, 
U.  S.  Dept.  Agr.) 

on  grass  or  small  grains,  but  its  migration  to  corn  or  from  field 
to  field  may  be  effectually  checked.  In  dry  weather  a  dust 
furrow  may  be  used  as  a  barrier  to  good  advantage.  Just  before 
harvest  plow  a  deep  furrow  around  the  field  to  be  protected, 
or  on  the  threatened  sides,  and  thoroughly  pulverize  the  soil  by 
dragging  a  heavy  log  back   and  forth  in  the  furrow,   making 


92         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  side  next  the  corn  as  steep  as  possible.*  In  attempting 
to  climb  this  barrier,  the  dust  will  slide  from  under  the  bugs 
and  large  numbers  will  accumulate  in  the  bottom  of  the  furrow, 
where  they  will  be  killed  by  the  heat  of  the  soil  if  it  has  a 
temperature  from  110°  to  120°  (air  temperature  of  over  90°). 
Keep  the  furrow  clean  by  dragging  a  log  through  it  now  and 
then.  By  sinking  post-holes  a  foot  deep  every  few  feet  in  the 
bottom  of  the  furrow  the  bugs  will  collect  in  them  and  may  be 
crushed  or  killed  with  kerosene.  Such  a  dust  furrow  will  be 
of  no  value  in  showery  weather,  and  is  most  effective  in  hot  dry 
weather  on  light  soil;  it  may  often  be  used  to  advantage  in 
combination  with  the  following  methods. 

In  place  of  the  dust  furrow  or  in  com])ination  with  it,  a  strip 
of  coaltar  is  often  run  around  the  field.  The  strip  should  be 
about  the  size  of  one's  fingei-,  which  can  be  made  l)y  pouring 
from  a  watering  can  with  the  mouth  stopped  down,  and  shoukl 
be  run  inside  the  dust  furrow  and  with  post-holes  sunk  along 
its  outer  edge.  Sometimes  it  is  run  in  a  zig-zag  Hne  with  the 
holes  at  the  inner  angles  so  that  the  bugs  will  be  concentrated 
at  the  holeg.  These  tar  strips  must  be  freshened  whenever  dust 
or  rubbish  covers  them.  The  soil  may  be  prepared  for  the  tar 
strip  ]3y  plowing  a  back  furrow  and  packing  the  top  with  a 
roller  or  beating  it  hard  with  spades;  or  a  strip  of  sod  may  be 
prepared  by  scraping  away  the  grass  with  a  farm  scraper  and 
then  smoothing  carefully  with  .shovels  or  hoes;  or  a  dead  furrow 
may  be  run  and  the  tar  strip  run  on  the  smooth  bottom.  To 
maintain  such  a  tar  strip  for  four  weeks  costs  about  $2  a  mile 
and  has  proven  itself  entirely  practical  and  effective. 

If  the  bugs  have  already  become  numerous  in  the  outer  rows  of 
corn,  most  of  them  may  be  destroyed  by  spraying  with  kerosene 
emulsion  (see  p.  4S)  made  to  contain  four  per  cent  kerosene,  apply- 
ing it  in  the  early  morning  or  towards  night.     It  costs  34  cents  a 

*  Such  a  furrow  may  possibly  be  made  more  readily  by  plowing  several 
furrows  and  harrowing  the  ground  thoroughly  until  reduced  to  a  fine  mulch 
and  then  plowing  a  dead  furrow  through  the  middle,  and  then  dragging  this 
with  a  log,  making  the  sides  as  steep  as  possible.  With  such  construction 
the  furrow  will  cost  about  three  cents  per  linear  rod. 


INSECTS   AFFECTING    GRAINS,   GRASSES,   FORAGE         93 

barrel  dilutctl,  and  a  man  will  spra}-  five  acres  per  day,  using  a 
barrel  per  acre.  Whale-oil  soap,  one-half  pound  to  the  gallon  of 
water,  has  proven  equally  effective  and  cost  $1.12  per  barrel. 

A  blast  torch,  for  which  an  attachment  is  furnished  with 
many  of  the  compressed-air  spraj'ers,  may  be  used  to  advantage 
for  destroying  the  Ijugs  in  a  dust  furrow  or  along  the  tar  line, 
or  a  spray  of  pure  kerosene  or  crude  petroleum  may  be  used  for 
the  same  purpose. 

Extensive  experiments  have  been  made  in  Illinois  and  Kansas 
with  the  use  of  the  muscardine  fungus  against  the  chinch-l)ug. 
Though  occasionally  the  residts  seem  to  ho  profitable,  and  though 
it  is  undoul)tedly  effective  in  wet  seasons  and  it  may  be  well 
to  distribute  the  fungus  to  places  where  it  does  not  occur  so 
that  it  may  reduce  the  numbers  of  the  bugs  in  wet  seasons, 
it  seems  to  be  of  very  little  value  in  dry  seasons,  when  the 
injury  is  worst,  and  cannot  l)e  relied  upon  to  check  the  increase 
of  the  pest  when  used  according  to  the  methods  so  far  devised. 

When  chinch-bugs  Ijccome  abundant  and  their  migration  to 
corn  seems  imminent,  the  farmer  should  prepare  to  devote  himself 
and  as  numy  hands  as  necessary  to  fighting  them  until  their 
advance  is  checked,  for  delay  will  mean  ruin,  while  the  prompt 
use  of  the  above  methods  will  save  the  corn  crop. 

Grasshoppers  or  Locusts  * 

Plagues  of  destructive  locusts — or  what  we  Americans  call 
grasshoppers — have  been  recorded  since  the  dawn  of  history. 
In  America  the  worst  devastation  was  done  by  the  flights  of 
the  Rocky  Mountain  or  Migratory  Locust  {Melanoplus  sprefus 
Thos.),  w^hich  swooped  down  upon  the  States  of  the  western 
part  of  the  Mississippi  Valley  in  the  years  1873  to  1S76  in  destruc- 
tive clouds. 

Concerning  their  recent  distribution,  numbers,  and  dcstruc- 
tiveness,  Mr.  W.  D.  Hunter  reported  after  the  season  of  1897: 
"  There  was,  this  season,  a  general  activity  of  this  species  through- 
out the  permanent  breeding  region  greater  than  at  any  time  in 
*  Various  species  of  the  family  Acrididoe. 


94       INSECT  PESTS   OF  FARM,  GARDEN  AND   ORCHARD 

many  years.  This  was  brought  about  by  a  series  of  dry  years, 
which  have  resulted  in  the  abandonment  of  farms  in  many  places. 
It  is,  of  course,  well  understood  that  the  absence  of  serious  damage 
since  1S76  has  been  partially  due  to  the  settUng  up  of  valleys  in 
the  permanent  region.  1  wish  to  make  it  clear,  however,  that  the 
dryness  is  the  primary  and  the  abandoning  a  secondary  cause." 

"  Serious  injury  has  occasionally  been  done  in  restricted 
locahties  in  Minnesota,  the  Dakotas,  Montana,  and  Manitoba, 
but  in  recent  years  it  has  been  difficult  to  find  the  species  except 
in  the  mountains,  and  it  will  probably  never  again  be  a  plague  in 
the  Central  States." 

The  Rocky  Mountain  Locust 

Let  us  first  consider  the  species  which  has  been  the  most 
injurious,  as  the  other  locusts  differ  from  it  in  but  few  essential 
points  other  than  in   being  non-migratory. 

To  correctly  understand  its  habits  the  reader  should  first 
divide  the  area  which  this  species  affected  into  three  parts.  Of 
these  the  (1)  Permanent  Region,  which  included  the  highlands  of 
Montana,  Wyoming,  and  Colorado,  formed  the  native  breeding- 
grounds,  where  the  species  was  always  found  in  greater  or  less 
abundance  ;*  (2)  the  Subpermanent  Region,  which  included  Man- 
itoba, the  Dakotas,  and  western  Kansas,  was  frequently  invaded; 
here  the  species  might  perpetuate  itself  for  several  years,  but 
disappeared  from  it  in  time;  (3)  the  Temporary  Region,  which 
included  the  States  bordering  the  Mississippi  River  on  the  west, 
was  that  only  periodically  visited  and  from  which  the  species 
generally  disappeared  within  a  year. 

Spread. — When  for  various  reasons  the  locusts  became  excess- 
ively abundant  in  the  Permanent  Region  they  spread  to  the 
Subpermanent  Region,  and  from  there  migrated  to  the  Tem- 
porary feeding-grounds.  It  was  the  latter  area  which  suffered 
most  severely  from  their  attacks,  but,  fortunately,  they  did 
not  do  serious  injury  the  next  A'ear  after  a  general  migration. 
In  the  Subpermanent  Region  their  injuries  were  more  frequent 
than  in  the  Temporary,  but  were  hardly  as  severe  or  sudden  as 
*  Bull.  25,  U.  S.  Dept.  Agr.,  Div.  Entomology.     C.  V.  Riley. 


INSECTS   AFFECTING   GRAINS.  GRASSES,  FORAGE 


95 


farther  east.  Migrating  from  their  native  haunts,  flights  of 
the  grasshoppers  usually  reached  southern  Dakota  in  early  sum- 
mer, Colorado,  Nebraska,  Minnesota,  Iowa,  and  western  Kansas 
during  midsummer,  and  southeastern  Kansas  and  Missouri 
during  late  summer,  appearing  at  Dallas,  Texas,  in  1874,  and  about 
the  middle  of  October,  and  even  later  in  1S76.  As  thus  indi- 
cated, the  flights  were  in  a  general  south  to  southeasterly  direction, 
while  west  of  the  Rockies  they  descended  to  the  more  fertile 
valleys  and  plains,  but  without  any  such  regularity  as  eastw^ard. 
While  the  rate  of  these  flights  was  variable  and  entirely  dependent 
upon  local  weather  conditions,  twenty  miles'  per  day  was  con- 
sidered a  fair  average.  The  flights  were  more  rapid  and  more 
distance  was  covered  in  the  early  part  of  the  season,  when,  while 


Fig.  62. — Rocky  Mountain  locust;  adult    and    different  stages  of    growth  of 
young.     (After  Riley.) 

crossing  the  dry  prairies,  a  good  wind  often  enabled  them  to  cover 

200  to  300  miles  in  a  day.     As  they  first  commenced  to  alight  in 

their  new  feeding-grounds  their  stay  was  limited  to  but  two  or 

three  da3's,  but  later  in  the  season  it  was  considerably  lengthened, 

and,  after  a  section  was  once  infested,  swarms  were  seen  to  be 

constantly  rising  and  dropping  during  the  middle  of  the  day. 

Life  History. — Over  all  the  infested  area,  and  while  still  sweep- 
ing it  bare  of  crops  and  vegetation,  the  females  commence  to  lay 
their  eggs,  and  continue  to  deposit  them  from  the  middle  of  August 
until  frost.  For  this  purpose  "  bare  sandy  places,  especially  on 
high,  diy  ground,  which  is  tolerably  compact  and  not  loose,"  are 
preferred.  "Meadows  and  pastures  where  the  grass  is  closely  grazed 
are  much  used,  while  moist  or  wet  ground  is  generally  avoided." 

In  such  places  the  female  deposits  her  eggs  in  masses  of  about 
thirty.  These  are  placed  about  an  inch  below  the  surface  in 
ft  pod-like  cavity,  which  is  lined  and  the  eggs  are  covered  by  a 


96 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


mucous  fluid  excreted  during  oviposition.  From  two  to  five  hours 
are  required  for  this  operation,  and  an  average  of  three  of  these 
masses  is  deposited  during  a  period  of  from  six  to  eight  weeks. 

As  the  time  of  ovipositing  varies  with  the  latitude,  so  the 
hatching  of  the  eggs  occurs  from  the  middle  or  last  of  March 
in  Texas  till  the  middle  of  May  or  first  of  June  in  Minnesota 
and  Manitoba.  Until  after  the  molt  of  the  first  skin,  and  often 
till  after  the  second  or  third  molt,  the  young  nymphs  are  con- 
tent to  feed  in  the  immediate  vicinity  of  their  birth.  When 
the   food    becomes    scarce    they    congregate    together    and    in 


Fig.  63. — Rocky  Mountain  locusts:  a,  a,  a,  females  in  different  positions, 
ovipositing;  h,  egg-pod  extracted  from  ground,  with  end  broken  open; 
c,  a  few  eggs  lying  loose  on  ground ;  d,  e,  show  the  earth  partially  removed, 
to  illustrate  an  egg-mass  already  in  place  and  one  being  placed;  /shows 
where  such  an  egg-mass  has  been  covered  up.     (After  Riley.) 

solid  bodies,  sometimes  as  much  as  a  mile  wide,  march  across 
the  country,  devouring  every  green  crop  and  weed  as  they  go. 
During  cold  or  damp  weather  and  at  night  they  collect  under 
rubbish,  in  stools  of  grass,  etc.,  and  at  such  times  almost  seem 
to  have  disappeared;  but  a  few  hours  of  sunshine  brings  theni 
forth,  as  voracious  as  ever.  When,  on  account  of  the  immense 
numbers  assembled  together,  it  becomes  impossible  for  all  to 
obtain  green  food,  the  unfortunate  ones  first  clean  out  the 
underbrush  and  then  feed  upon  the  dead  leaves  and  bark  of 
timber  lands,   and  have  often  been  known  to  gnaw  fences  and 


INSECTS   AFFECTING   GRAINS,   GRASSES,    FORAGE         97 

frame  buildings.  Stories  of  their  incredible  appetites  are  legion; 
a  friend  informs  me  that  he  still  possesses  a  rawhide  whip  which 
they  had  quite  noticeably  gnawed  in  a  single  night! 

l^y  mathematical  computation  it  has  been  shown  that  such 
a  swarm  could  not  reach  a  point  over  thirty  miles  from  its 
birthplace,  and  as  a  matter  of  fact  they  have  never  been  known 
to  proceed  over  ten  miles. 


Fig.  64. — A  swarm  of  grasshoppers  attacking  a  wheat-field.     (After  Riley.) 

As  the  nymphs  become  full  grown  they  are  increasingly 
subject  to  the  attacks  of  prcdaccous  birds  and  insects,  insect 
parasites,  fungous  and  l^acterial  diseases,  and  are  also  largely 
reduced  ])y  the  canniljalistic  appetites  of  their  own  numl^ers. 
When  the  mature  nymphs  transform  to  adult  grasshoppers  and 
thus  become  winged,  large  swarms  are  seen  rising  from  the 
fields  and  flying  toward  their  native  home  in  the  Northwest. 


98        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

This  usually  takes  place  during  June  and  early  July  in  the 
North,  and  as  early  as  April  in  Texas,  so  that  it  is  frequently 
impossible  to  distinguish  the  broods  of  the  temporary  region 
from  the  incoming  brood  which  has  migrated  from  the  permanent 
region.  Although  the  eggs  for  a  second  brood  are  sometimes 
laid,  these  seldom  come  to  maturity,  and  the  species  is  essen- 
tially single-brooded. 

The  Lesser  Migratory  Locust 

Besides  the  Rocky  Mountain  locust  there  is  only  one  other 
species  that  truly  possesses  the  habit  of  migrating,  though  to 
a  far  lesser  extent,  and  which  is  therefore  known  as  the  Lesser 
Migratory  Locust  (Melanoplus  atlaniis  Riley).  It  is  considerably 
smaller  than  its  western  relative  and  somewhat  resembles  the 
red-legged  locust  both  in  size  and  appearance.  The  species 
is  very  widely  distributed,  occurring  from  Florida  to  the  Arctic 
Circle  east  of  the  Mississippi,  and  on  the  Pacific  slope  north  of 
the  fortieth  parallel  to  the  Yukon.  The  habits  and  life  history 
of  the  species  are  in  all  essentials  practically  the  same  as  the 
former  species,  except  that  they  have  no  particular  breeding- 
grounds.  Injuries  by  this  grasshopper  were  first  noticed  in 
1743,  almost  seventy-five  years  before  the  first  record  of  the 
Rocky  Mountain  locust,  and  since  then  it  has  done  more 
or  less  serious  damage  in  some  part  of  the  territory  inhabited 
every  few  years. 

Non-migratory  Locusts 

There  are  several  species  of  locusts  which,  though  lacking 
the  migratory  habit,  and  thus  being  more  easily  controlled, 
often  become  so  numerous  as  to  do  serious  damage  over  limited 
areas.  Both  as  regards  the  regions  inhabited,  its  habits,  and 
life  history,  the  common  Red-legged  Locust  {Melanoplus  femur- 
ruhrum  Har.)  hardly  differs  from  the  last  species,  and  is  often 
found  in  company  with  it.  It  is  non-migratory,  however,  and 
though  the  damage  it  does  is  thus  entirely  local,  it  is  often  of 
considerable  importance. 


INSECTS  AFFECTING  GRAINS,  GRASSES,   FORAGE 


99 


Fig.  65. — Red-legged  locu.'^t 
(Melanoplus  femur  -  rubritm 
Harr.).     (After    Riley.) 


Records  of  locust  plagues  in  California  date  back  as  far  as 
1722.  Many  of  them  were  doubtless  due  to  the  California 
Devastating  Locust  {Melanoplus  devastator  Scud.),  and  in  the 
last  invasion  of  1885  this  species  outnumbered  all  others  seven 
to  one.  Resembling  the  last  two 
species  in  size  and  markings,  the 
habits  and  life  history  of  this  species 
are  also  supposed  to  be  similar  to 
them,  though  they  have  not  as  yet 
been  thoroughly  studied. 

Together  with   the   last    species 
the      Pellucid      Locust       (Caninida 

pellueida  Scud.)  has  been  largely  responsible  for  the  losses  occa- 
sioned by  locusts  in  California,  and  has  also  l)een  found  in  New 
England,  but  is  not  noted  there  as  specially  destructive. 

Our  largest  winged  Amer- 
ican locust,  the  American 
Acridium  (Schistocerca  ameri- 
cana  Scud.),  is  practically 
confined  to  the  Southern 
States  from  the  District  of 
Columbia  to  Texas,  and  thence 
south  through  Mexico  and 
Central  America,  being  rarely 
found  in  the  North.  This 
species  is  essentially  a  tropical 
r.^  ao     ^u       11    •]  1    "^^  /^^         1     one,  and  has  often  been   ex- 

riG.  6G. —  Ihe  pellucid  locu.st  {Camnula  \  . 

pellueida 'S>Q,\id.).     (After  Emerton.)        ceedingly    destructive,     being 

especially  so  in  1876  in 
]\Iissouri,  Tennessee,  North  Carolina,  Georgia,  and  southern  Ohio. 
Considerably  larger  than  the  preceding  species  are  the  Dif- 
ferential Locust  (Melanoplus  differentialis  Thos.)  and  the  Two- 
striped  Locust  (Melanoplus  hivittaius  Scud.),  of  which  the  former 
is  peculiar  to  the  central  States  of  the  Mississippi  Valley,  Texas, 
New  Mexico,  and  California,  while  the  latter  has  a  more  extended 
range  from  Maine  to  Utah  and  as  far  south  as  Carolina  and 


100      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Texas.     These   two    differ   from   the   smaller   species   in   laying 
only  one  or  two  masses  of  eggs,   and  the  eggs  of  differentialis 


Fig.   67. — The  American   acridium   {Schistocerca   americana   Scud.),     (.\fter 

Riley.) 

have  often  been  found  placed  under  the  bai'k  of  logs,  but  other- 
wise their  habits  are  very   similar.      The   two-striped  locust  is 

characterized  by  two  yel- 
lowish stripes  extending 
from  the  eyes  along,  the 
sides  of  the  head  and 
thorax  to  the  extremities 
of   the    wing-covers,   and 

Fig.    68.-The     Two-striped     locust    (Mela-  ''     P'°^^^^>^     ^^'^     ^P^"'' 
nophis   bivittatus   Scud.).     (After  Riley.)       ^OSt  commonly  observed 

by  the  farmer. 

The  Differential  Locust. — Throughout  the  Mississippi  Valley 

from  Illinois  southward,  the  Differential  Locust  *  is  one  of  the 


Fig.  69. — The  Differential    locust  (Melanoplus  differentialis  Thos.).     (After 

Riley.) 

most  common  and  destructive  grasshoppers,  and  is  an  excellent 
example  of  several  of  our  more  abundant  and  injurious  species 
which  have  very  similar  habits. 

*  Melanoplus  differentialis  Thos. 


INSECTS  AFFECTING   GRAINS,  GRASSES,  FORAGE       101 " 

The  little  grasshoppers  hatch  about  the  middle  of  May,  from 
eggs  which  were  laid  in  the  fall,  though  we  have  observed 
them  in  March  in  Central  Texas,   and   are  of  a  dusky  brown 


Fig.  70. — The  southern  lubber  grasshopper  {Dictyophorus  reticulatus) :  nymph^ 
and  adult,  slightly  enlarged. 

Lolor,  marked  with  yellow.     The  head  and  legs  are  the  most 

prominent  feature  of  the  young  nymphs.     During  their  subse- 

([uent  growth  they  molt  five  times  at 

intervals  of  ten  days  to  two  weeks,  the 

relative    size    and  appearance  of  the 

different   stages  being  shown   in  Fig. 

72.      Professor   H.   A,    Morgan,    who 

made  a  careful  study  of  an  outbreak  Fig.    71.— Egg-mass    of    the 

.        .  differential  locust — enlarged. 

of  this  species  m  Mississippi  m  1900, 

has  given  an  interesting  account  of  their  growth  and  habits. 

"  The  young   on   first   emerging   from  the   eggs   are   sordid 

white  and  after  an  airing  of  an  hour  or  two,  are  darker,  assuming 


102     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  72. — Nymphs  of  the  differential  locust 
in  different  stages  (1  to  5)  of  growth — 
all  enlarged. 


INSECTS  AFFECTING  GRAINS,   GRASSES,  FORAGE         103 

a  color  not  unlike  the  dark-gra}'  alluvial  soil  over  which  they 
feetl.  There  are  changes  of  color  as  the  earlier  stages  are  assumed, 
but  until  the  close  of  the  third  stage  these  changes  are  not 
readily  perceptible  in  the  field  to  the  naked  eye.  At  tlie  close 
of  stage  four  the  greenish  yellow  color  becomes  prominent  on 
many  forms,  and  in  stage  five  the  greenish  yellow  and  yellow 
brown  colors  predominate.  The  vigorous  feeding  and  rapid 
growth  of  the  young  in  stages  four  and  five,  and  the  promi- 
nence of  the  wing-pads  in  stage  five,  cause  the  grasshoppers 
in  these  conditions  to  appear  almost  as  conspicuous  as  adults. 

''  The  habits  of  the  young  are  interesting,  and  a  knowledge 
of  some  of  them  may  be  helpful  in  developing  remedies.  After 
hatching  they  remain  for  several  hours  in  close  proximity  to 
the  egg-pod  from  which  they  emerged.  With  this  period  of 
faint-heartedness  over,  they  may  venture  out  for  a  few  yards 
each  day  into  the  grass,  weeds,  or  crop  neighboring  the  egg-area. 
Upon  being  disturbed  they  invariably  make  the  effort  to  hop 
in  the  cHrection  of  the  so-called  nest.  Nymphs  emerging  from 
eggs  on  a  ditch  bank,  if  forced  into  the  water,  will  seldom  make 
the  effort  to  reach  the  other  side,  but  will  turn  back  to  the  bank 
from  which  they  were  driven.  As  development  takes  place  the 
extent  of  their  peregrinations  into  the  crop  is  easily  traced  by 
the  shot-hole  appearance  of  the  leaves  upon  which  they  feed. 
The  tender  leaves  of  cocklebur  are  always  preferred  by  the 
grasshoppers  in  the  early  stages.  Young  Bermuda  grass  is  also 
a  favorite  food,  and  succulent  grasses  of  all  kinds  are  freely 
eaten.  In  the  third,  fourth,  and  fifth  stages,  as  grass,  weeds, 
and  even  shrubs  disappear  along  the  ditch  banks  and  bayous, 
the  crops  of  corn  and  cotton  adjacent  begin  to  show  signs  of 
vigorous  attack,  and  the  march  of  destruction  commences.  ...  A 
few  hours  before  molting  the  grasshoppers  tend  to  congregate 
and  become  sluggish.  Molting  varies  as  to  time,  and  slightly 
as  to  manner,  with  different  stages.  In  the  early  stages  less 
time  is  required  and  the  operation  occurs  on  the  ground  or  upon 
low  bunches  of  grass  and  weeds.  Every  effort  of  the  grass- 
hoppers at  this  time  seems  to  be  to  avoid  ccnspicuity,  and  in 


104       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


doing  so  spare  themselves,  in  a  manner,  enmity  of  parasites. 
After  the  molting  of  the  first,  second,  and  third  stages  it  is  not 
long  before  the  young  grasshoppers  are  sufficiently  hardened  to 
begin  feeding  again,  but  after  the  molt  of  the  fourth  and  fifth 
stages,  particularly  the  last  molt,  some  time  is  required  to 
extend  the  wings  and  dry  and  harden  the  body  before  feeding 

is  resumed.  The  last  molt 
usually  occurs  on  the  upper 
and  well-exposed  leaves  of 
corn  and  other  plants  upon 
w^hich  they  may  be  feeding, 
though  it  is  not  uncommon 
for  the  grasshoppers  to  drop 
to  the  ground  during  the 
maneuvers  of  the  process. 
The  reason  for  the  selection 
of  the  more  exposed  leaves 
for  the  last  molt  is  obvious. 
The  bodies  are  large,  and 
rapid  drying  protects  them 
from  fungous  diseases  which 
lurk  in  the  more  shaded 
and  moist  sections  during 
the  months  of  June  and 
July.  The  last  prominent 
habit  to  which  we  call  at- 
tention is  that  of  the  fully 
grown  grasshopper-6  to  seek 
the  shade  offered  by  the 
growing  plants  during  the 
hottest  part  of  the  day." 
The  hoppers  become  full  grown  about  the  first  of  July.  The 
adult  is  about  IJ  inches  long,  its  wings  expand  2^  inches,  and 
it  is  of  a  bright  yellowish-green  color.  The  head  and  thorax 
are  olive-brown,  and  the  front  wings  are  of  much  the  same  color, 
without  other  markings,  but  with  a  brownish  shade  at  the  base; 


Fig.  73. — Differential  locust:  last  stage  of 
nympli  with  its  cast  skin  on  tip  of  com 
plant. 


INSECTS  AFFECTING  GRAINS,   GRASSES,   FORAGE  105 

the  hind-wings  are  tinged  with  green;  the  hind-thighs  are  bright 
yellow,  especially  below,  with  four  black  marks;  the  hind-shanks 
are  yellow  with  black  spines  and  a  ring  of  the  same  color  near 
the  base.  The  adults  at  once  attack  whatever  crops  are  avail- 
able, often  finishing  the  destruction  of  those  injured  by  them  as 
nymphs,  but  in  a  few  days  their  appetites  seem  to  become  some- 
what appeased  and  they  commence  to  mate  and  wander  in  search 
of  suitable  places  for  laying  the  eggs.  Relatively  few  eggs  are 
laid  in  cultivated  ground,  the  favorite  places  being  neglected  fields 
grown  up  in  grass  and  weeds,  the  edges  of  cultivated  fields,  private 
roadways,  banks  of  ditches  and  small  streams,  and  pasture  lands. 
Alfalfa  land  is  a  favorite  place  for  oviposition,  and  alfalfa  is 
frequently  seriously  injured  by  this  species.  It  is  doubtless  clue 
these  egg-laying  habits  and  the  abundance  of  food  on  uncultivated 
land  that  this  species  always  increases  enormously  on  land 
which  has  been  flooded  and  then  lies  idle  for  a  }-ear  or  two. 
Most  of  the  eggs  are  laid  in  August  and  early  September.  Each 
female  deposits  a  single  egg  mass  of  about  100  eggs  just  beneath 
the  surface  of  the  soil.  During  this  season  the  females  may 
frequently  be  found  with  the  abdomens  thrust  deep  in  the 
soil,  as  the  process  of  egg-laying  requires  some  time.  The 
eggs  are  yellow  and  arranged  irregularly  in  a  mass  which  is 
coated  with  a  gluey  sul)stance  to  which  the  earth  adheres,  which 
protects  them  from  variable  conditions  of  moisture  and  tem- 
perature. 

Enemies. — As  before  mentioned,  large  numbers  of  the  nymphs 
are  destroyed  before  reaching  maturity  by  their  natural  enemies. 
Among  these  a  minute  fungus  undoubtedly  kills  many  of  those 
already  somewhat  exhausted,  especially  during  damp  weather. 
Almost  all  of  our  common  birds,  as  well  as  many  of  the  smaller 
mammals,  are  known  to  feed  quite  largely  upon  them. 

A  small  red  mite  (Ti-ombidium  locustarum  Rile}^,  somewhat 
resembling  the  common  red  spider  infesting  greenhouses,  is 
often  of  great  value  not  only  in  killing  the  nymphs  by  great 
numbers  of  them  sucking  out  the  life-juices  of  the  young  hopper, 
but  also  in  greedily  feeding  upon  the  eggs. 


106        INSECT  PESTS  OF   FARM,  GARDEN  AND  ORCHARD 

The  maggots  of  several  species  of  Tachina-flies  are  of  con- 
siderable value  in  parasitizing  both  nymphs  and  adult  locusts. 
Their  eggs  are  laid  on  the  nock  of  a  locust,  and,  upon  hatching, 


^  ^        c        V         -     d 

Fig.  74. — A  Locust-mite  {Trombidium  locustaruni):  a,  the  larva  as  seen  on 
locust's  wing;  c,  male  mite;  d.  female,  the  two  latter  appearing  as  when 
egg-destroyers — all  greatly  enlarged.     (After  Riley.) 

the  maggots  pierce  the  skin  and  live  inside  by  absorbing  its 
juices  and  tissues.  When  full  grown  the  maggots  leave  the 
locust,   descend  into   the   earth,    and   there   transform   to   pupae 


Fig.  75. — Anthomyia  egg-parasite,     a,  fly;  b,  puparium;  c,  larva;  d,  head  of 
larva.     (After  Riley.) 

inside  of  their  cast  skins,   and  from  the  pupae  the  adult  flies 
emerge  in  due  time. 

The  maggots  of  one  of  the  Bee-flies   (Systoechus  oreas)   feed 
upon  grasshopper  eggs,  but  their  life  history  is  not  fully  known. 


INSECTS   AFFECTING   GRAINS,  GRASSES,   FORAGE        107 


The    coninion  Flesh-fly  (Sarcophaga   carnaria   Linn.),  Fig.  77,  is 
also  very  destructive,  though  hirgely  a  scavenger. 


Fig.   76. — Two   tachina-flies.     {Exoristn   leiicnnioe   Kirk,    and   E.  flavicauda 
Riley).     (After  Riley.) 

But  of  all  the  insects  attacking  locusts,  the  l^hster-beetles, 
which,  unfortunately,  are  often  known  to  us  as  very  injurious 
to  various  garden  crops,  are 
probably  of  the  most  value. 
The  female  beetle  deposits 
from  four  to  five  hundred  of 
her  yellowish  eggs  in  irregular 
masses  in  loose  ground,  and 
in  about  ten  days  there  hatch 
from  these  eggs  some  ''  very 
active,  long  -  legged  larvae, 
with  huge  heads  and  strong 
jaws,  which  run  about  everywhere  seeking  the  eggs  of  locusts." 
Each  of  these  larva?  will  consume   one   of  the  masses  or  about 


Fig.  77. — Common  flesh-fly  (Sarco- 
phaga carnaria  lAnn.):  a,  larva;  b, 
pupa;  c,  fly.  Hair-lines  show  natural 
size.     (After  Riley.) 


(^^_tt^«.        W^^        t^lj-    ,iy^^        -.-^^ 
Fig.  78. — Various  stages  of  a  blister-beetle  (Epicauta  vittata).     (After  Riley.) 

thirty  eggs.  The  subsequent  life  history  of  these  insects  is  very 
complicated  on  account  of  their  peculiar  habits,  but  the  various 
stages  are  shown  in  Fig.  78. 


108       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Control. — As  the  eggs  are  usually  laid  in  the  ground  in  the 
fall,  deep  plowing  in  late  fall  or  early  spring  effectually  buries 
them  too  deep  for  the  young  nymphs  to  emerge.  On  alfalfa 
land  thorough  disking  is  often  used  for  the  same  purpose. 
Thorough  harrowing  in  the  fall  so  as  to  pulverize  the  soil  for 
the  depth  of  an  inch  will  break  up  many  of  the  egg  masses, 
though  it  is  not  as  sure  a  control  as  plowing  them  under. 

When  the  young  emerge,  they  may  sometimes  be  destroyed 
by  burning  over  stubble,  grass  and  rubbish  where  it  is  present 
in  sufficient  quantites,  or  by  augmenting  it  with  straw,  which 
may  be  done  to  advantage  on  cold  days  when  the  nymphs  are 
congregated  in  such  shelter.  If  the  surface  of  the  ground  is 
smooth  and  hard  many  may  be  killed  by  the  use  of  a  heavy 
roller,  jDarticularly  in  the  morning  and  evening,  when  they  are 
sluggish  in  their  movements.  Plowing  a  badly  infested  field 
in  a  square,  working  toward  the  centre  so  as  to  drive  the  young 
nymphs  inward,  will  result  in  l)urying  many  of  them  in  the  furrows, 
and  the  last  may  be  burned  or  trapped  in  holes  as  described 
below.  Simple  ditches  2  feet  wide  and  2  feet  deep  form 
effectual  barriers  for  the  young  hoppers.  The  sides  next  to  the 
crop  to  be  protected  should  be  kept  finely  pulverized  by  hauling 
a  log  or  a  brush  of  dead  branches  through  the  ditch.  The  ditch 
may  be  made  as  described  for  chinch-bugs  and  is  handled  in 
the  same  manner,  the  little  hoppers  drifting  to  the  bottom  of 
the  ditch,  where  they  are  killed  by  the  heat  on  a  hot  day  or 
where  they  are  caught  in  post-holes  sunk  every  few  feet  in  the 
bottom  of  the  ditch.  This  method  may  be  used  to  advantage 
in  plots  of  corn,  cotton,  or  garden  truck  which  has  already 
become  infested,  by  running  furrows  around  the  field  and  occa- 
sionally through  it,  and  then  driving  the  young  hoppers  toward 
them,  which  may  be  readily  done  by  a  number  of  children  armed 
with  branches.  Where  ditches  containing  water  are  available 
the  young  hoppers  may  be  very  effectively  destroyed  by  oiling 
the  surface  of  the  water  with  kerosene  emulsion  (p.  48)  and 
then  driving  them  into  the  ditches,  for  even  if  they  succeed  in 
crawling  out  they  will  succumb  to  the  oil. 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE        109 

Where  the  young  hoppers  have  congregated  in  large  numbers 
on  the  edge  of  fields,  in  patches  of  weeds,  etc.,  they  ma}'  be 
destroyed  by  spraying  them  with  kerosene  or  crude  petroleum 
either  pure  or,  preferably,  in  an  cnuUsion,  and  the  weeds  and 


Fig.  79. — Simple  coal-oil  pan  or  hopperdozer.     (After  Riley.) 


Fig.  so. — The  Price  oil-pan  or    hopperdozer,  with  partitions    to  prevent 
slopping.     (After  Riley.) 

grass  along  fences  and  in  neglected  fields  should  be  thoroughly 
treated  with  a  strong  arsenical  spray  or  dust. 

In  pastures,  small  grains  or  any  crops  permitting  their  use, 
immense  numbers  of  the  nymphs  may  be  caught  by  the  use 


no       INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE        111 

of  hopperdozers,  which  may  be  utilized  where  the  use  of  poisoned 
bran  would  not  be  possible.  The  hoppcrdozer  consists  of  a 
shallow  pan  containing  water  with  a  surface  of  kerosene,  crude 
petroleum,  or  coal  tar,  which  is  sometimes  used  without  water. 
The  pan  is  mounted  on  runners  or  wheels  and  if  larger  than  about 
3  feet  square  is  usually  provided  with  partitions  to  prevent 
slopping.  The  back  and  sides  are  high  and  sometimes  are  made 
of  canvas.  "  A  good  cheap  pan  is  made  of  ordinary  sheet 
iron,   8  feet  long,    11   inches  wide   at  the  bottom,   and  turned 


Fig.  82. — Carolina  locust  killed  by  fimgous  disease.     (Photo  by  Weed.) 

up  a  foot  high  at  the  back  and  an  inch  high  in  front.  A 
runner  at  each  end,  extending  some  distance  behind,  and  a 
cord  attached  to  each  front  corner,  complete  the  pan  at  a  cost 
of  about  $1.50  (Fig.  80).  We  have  known  of  from  seven  to 
ten  bushels  of  young  locusts  caught  with  one  such  pan  in  an 
afternoon.  It  is  easily  pidled  by  two-  boys,  and  by  running 
several  together  in  a  row,  one  l^oy  to  each  rope,  and  one  to 
each  contiguous    pair,    the    best    work    is    performed  with    the 


112        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

least  labor."  Larger  pans  are  drawn  or  pushed  by  horses.  The 
oil  is  best  used  on  the  surface  of  water,  from  which  the  insects 
are  removed  with  a  strainer,  and  any  which  hop  out  will  die 
after  having  come  in  contact  with  the  oil. 

Destroying  the  Adults. — The  destruction  of  the  winged  insects 
is  an  entirely  hopeless  task,  for,  though  even  large  numbers 
are  caught,  so  many  will  remain  that  the  damage  done  the 
crops  would  be  but  very  slightly  diminished.  One  of  the  most 
promising  means  for  averting  the  swarms  of  winged  migratory 
locusts  from  alighting  in  the  fields  is  by  a  dense  smudge,  in 
which  some  foul-smelling  substances  are  placed.  Where  strictly 
attended,  and  with  favorable  winds,  this  has  often  proved  highly 
successful.  To  accomplish  the  best  results  farmers  over  an 
extensive  area  should  combine  in  its  use. 

The  South  African  Fungus. — In  1900  Professor  Morgan  made  a 
test  of  a  fungous  disease  which  had  been  found  to  destroy  large 
numbers  of  grasshoppers  in  South  Africa,  to  determine  whether, 
after  starting  it  ])y  artificial  propagation,  it  would  spread  suffi- 
ciently to  destroy  any  considerable  number  of  locusts.  The 
weather  was  favorable,  rains  being  frequent.  Early  in  August 
it  was  found  that  "  over  the  areas  where  the  liquid  infection 
was  spread  diseased  hoppers  were  abundant."  "  As  many  as 
a  dozen  dead  grasshoppers  could  be  found  upon  a  single  plant, 
and  some  upon  nearly  every  weed  on  ditch-banks  where  grass- 
hoppers were  numerous.  From  the  centres  of  infection  great 
areas  had  become  inoculated,  spreading  even  beyond  the  planta- 
tions first  infected."  The  property  upon  which  it  was  placed 
became  thoroughly  infected  with  the  fungus.  Strangely,  though 
many  other  species  of  grasshoppers  were  abundant,  only  the 
differential  locust  was  killed  by  it.  Dr.  Howard  states  that  this 
disease  has  also  spread  and  done  effective  work  in  Colorado. 
However,  more  recent  experiments  made  by  the  writer  in  Texas 
gave  only  negative  results,  and  it  is  doubtful  if  any  reliance  can 
be  placed  upon  the  artificial  use  of  such  fungous  diseases  for 
locust  control. 

Poisoning. — A  mash  composed  of  bran,  molasses,  water,  and 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE         113 

arsenic  or  Paris  green^  which  has  been  extensively  used  for  cut- 
worms, was  found  to  be  quite  successful  in  the  experiments 
of  Mr.  D.  W.  Coquillct  in  the  San  Joaquin  Valley,  California, 
during  1885,  for  protecting  orchards,  vineyards,  gardens,  etc., 
and  might  even  be  of  some  value  for  grain  crops.  Two  pounds 
of  Paris  green,  25  pounds  of  bran,  Imrely  moistened  with 
water  and  cheap  molasses,  will  be  aljout  the  correct  propor- 
tion. It  should  be  placed  in  the  fields,  a  tablespoonful  to 
each  plant  or  vine.  At  this  rate  the  cost  per  acre  of  vineyard, 
including  labor,  will  not  exceed  fifty  cents.  The  poison  acts 
slowly,  but  if  judiciously  used  will  l^e  found  very  effective, 
especially  for  the  non-migratory  forms.  In  Texas  the  mash 
has  been  found  satisfactory  in  destroying  the  grasshoppers 
attacking  cotton.  One  planter  writes:  ''  We  are  successfully 
using  arsenic  (for  grasshoppers)  at  the  following  rates :  10  pounds 
of  wheat  hran,  H  gallons  sorghum  molasses,  1  pound  arsenic. 
Make  a  thick  mash,  sow  broadcast  on  infected  ground,  and 
it  will  surely  kill  them.  I  used  40  pounds  last  year  and  made 
49  bales  of  cotton.  My  neighbors  did  not  do  anything  and 
entirely  lost  their  crop."  The  writer  has  also  seen  excellent 
results  from  the  use  of  the  mash  in  Texas  with  only  one  pound  of 
poison  to  25  pounds  of  bran.  However,  Professor  Morgan  con- 
cluded that  "  the  mash  cannot  be  relied  upon  in  severe  outbreaks, 
such  as  occurred  in  the  delta,  but  may  be  used  in  limited  attacks 
where  the  area  affected  would  not  warrant  the  more  aggressive 
methods." 

"  When  grasshoppers  are  young  or  half-grown,  a  poisonous 
bait,  known  as  the  C riddle  Mixture,  has  proved  effective  in 
many  parts  of  the  countr}'  (particularly  for  the  Rocky  Mountain 
locust).  This  consists  of  one  part  of  Paris  green  and  about 
one  hundred  parts  of  fresh  horse  manure,  by  measure.  Enough 
water  is  added  to  make  the  mass  soft  without  being  sloppy. 
It  can  be  taken  to  the  field  b}'  a  wagon  or  stone  boat  and 
scattered  about  by  means  of  a  paddle." — Washburn. 


114        INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


The  Army  Worm* 

Almost  every  year  some  locality  repoi'ts  serious  injury  to 
crops  by  armies  of  caterpillars,  which  have  not  been  previously 
known  for  many  j-ears.  This  being  the  case  the  farmers  are 
at  a  loss  to  combat  them,  and  by  the  time  information  has  been 
secured  the  pests  have  completed  the  damage.  The  Army 
Worm  occurs  throughout  the  United  States  east  of  the  Rocky 
Mountains  and  lives  in  low,  rank  growths  of  grass,  which  form 
the  normal  breeding-grounds.  When  from  an  abundance  of 
such  food,  or  through  failure  of  the  parasites  to  prevent  their 

increase,  the  caterpillars  be- 
come overabundant,  they  as- 
sume the  army  habit  and 
march  en  masse,  consuming 
all  in  their  path. 

The  next  3'ear  their  natural 
enemies  will  usually  have  them 
under  control  again  and  there 
will  be  but  little  damage,  and 
then  they  will  not  be  observed 
as  injurious  for  a  series  of 
years,  though  the  moths  are 
always  fairly  common. 

Life  Historij. — In  the  North 
the  moths  appear  early  in  June 
and  the  females  lay  the  small  yellowish  eggs  in  rows  of  from 
ten  to  fifty  in  the  unfolded  bases  of  the  grass  leaves,  covering 
them  with  a  thin  layer  of  glue.  Over  seven  hundred  may  be 
deposited  by  one  female,  so  that  when  the  young  caterpillars 
hatch  in  about  ten  days,  the  progeny  of  a  few  moths  might 
form  a  quite  destructive  army.  The  worms  usually  feed  entirely 
at  night,  and  thus  whole  fields  will  sometimes  be  ruined  before 
they  are  discovered,  though  a  few  generally  feed  by  day,  as 
they  all  do  in  cloudy  weather.     The  leaves  and  stalks  of  grains 

*  Lcucania  uiiipuncta  Haworth.     Family  Nocluida:, 


Fig.  83. — Army-worm  moth  {Leucania 
unipuncta),  pupa,  and  eggs  in  natural 
position  in  a  grass-leaf.  Natural  size. 
(After  Comstock.) 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE        115 


Fig.  84. — Army  worms  at  work  on  corn-plant.     (After  Slingerland.) 


IIG        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  grasses  form  their  favorite  food,  the  heads  usually  being 
cut  off,  but  various  garden  crops  are  often  seriously  injured  if 
they  happen  in  their  path.  Though  usually  untouched,  even 
clover  is  not  exempt.  In  from  three  to  four  weeks  the 
worms  have  become  full  grown  and  are  then  about  1^  to  2 
inches  long,  of  a  dark  gray  or  dingy  black  color,  with  three 
narrow,  3'ellowish  stripes  above,  and  a  slightly  broader  and 
darker  one  on  each  side,  quite  resembling  cutworms,  to 
which  they  are  nearly  related.  They  now  enter  the  earth  and 
transform  to  pupa?,  from  which  the  adult  moths  emerge  in  about 

two  weeks.  These  lay  eggs 
for  another  brood  of  worms 
which  appear  in  September, 
but  are  very  rarely  injuri- 
ous. The  moths  which  de- 
velop from  this  last  brood 
either  hibernate  overwinter, 
or  deposit  eggs,  the  larvae 
from  which  become  partially 
grown  before  cold  weather 
and  then  hibernate.  In 
either  case  the  young  larvse 
feed  in  the  spring,  not  usu- 
ally doing  much  damage, 
pupate  in  May,  and  the 
moths  of  the  first  genera- 
tion appear  in  June  as 
Thus  in  the  North  there  are  three  broods 
a  year,  the  young  larvse  usually  hibernating,  while  in  the. 
South  there  may  be  as  many  as  six  generations,  and  the 
moths  usually  hibernate  over  winter  and  lay  their  eggs  in  the 
spring. 

The  moths  very  often  fly  into  lights  and  are  among  the  com- 
monest of  our  pla'n  "  millers."  The  front  wings  are  a  clay  or 
fawn  color,  specked  with  black  scales,  marked  with  a  darker 
shade  or  stripe  at  the  tips,  and  with  a  distinct  spot  at  the  centre, 


Fig.  85. — An  army 
w  o  r  m — a  bout 
one -third  en- 
larged. (After 
Chittenden,  U.  S. 
Dept.  Agr.) 

already  described 


Fig.  86. — a,  head 
of  fall  army 
worm;  b,  head  of 
army  worm  — 
enlarged.  (After 
Chittenden,  U.  S. 
Dept.  Agr.) 


INSECTS  AFFECTING  GRAINS,   GRASSES,  FORAGE         117 

which  gives  the  specific  name  wiipuncta.      The  hind-wings  are 
somewhat  Hghter  with  blackish  veins  and  darker  margins. 

Enemies. — Were  it  not  for  other  insects  which  pre}'  upon  the 
army  worm,  the  army  hal^it  woiikl  doubtless  be  more  often 
assumed  and  we  should  have  to  deal  with  them  more  frequently. 
Ordinarily,  however,  the  parasitic  and  predaceous  insects  hold 
them  in  check  very  efficiently  and  when  an  outbreak  does  occur, 
the  later  broods  of  the  same  season  are  often  entirely  destroj'cd  by 
their  insect  enemies.     Large  numbers  are  always  destroyed  by  the 


Fig.  87. — ^The  farmer's  friend,  the  red-tailed  tachina-fly  (Winthernia  i-pustv^ 
lata):  a,  natural  size;  b,  much  enlarged;  c,  army  worm  on  which  fly 
has  laid  eggs,  natural  size;  d,  same,  much  enlarged,     (.\fter  Slingerland.) 


predaceous  ground-beetles  and  their  larva3  (p.  14),  but  their 
most  deadly  enemies  are  the  tachina-flies  (p,  106).  These  lay 
from  a  dozen  to  fifty  eggs  on  a  caterpillar,  and  the  maggots 
from  them  enter  the  body  and  absorb  the  juices  and  tissues  of 
the  host,  thus  soon  killing  it.  When  feeding  at  night  the  worms 
are  ordinarih"  free  from  these  parasites,  but  when  the  marching 
habit  is  assumed  the  flies  swarm  around  them  on  cloudy  days 
and  before  the  next  year  they  again  have  the  remnants  of  the 
voracious   army  under  subjection.     Therefore,  worms  with  the 


118        INSECT  PESTS  OF   FARM,   GARDEN  AND  ORCHARD 

tachina-fly  eggs  on  tliera  (Fig.  87)  should  never  be  destroyed 
where  avoidable. 

Control. — When  detected,  all  efforts  should  be  centred  on 
keeping  the  worms  out  of  crops  not  yet  attacked  and  confining 
their  injury  to  as  small  an  area  as  possible.  As  a  barrier  to 
their  progress,  there  is  nothing  better  than  a  dust  furrow  made 
as  already  described  for  chinch-bugs  (p.  91),  two  or  three  of 
which  may  be  found  necessary  in  cool  weather  or  where  a  fine 
dust  cannot  be  maintained. 

Deep  fall  plowing  and  thorough  harrowing  will  be  effective 
against  the  hibernating  larva?,  as  will  the  burning  of  all  grass 
along  ditches,  fences,  and  spots  where  the  larvae  normally  live. 

By  thorough  spraying,  or  perhaps  better  by  dusting,  a  strip 
of  the  crop  with  Paris  green  or  some  arsenical,  and  liberally 
distributing  poisoned  bran  mash  (see  p.  47),  large  numbers 
may  be  destroyed.  Where  they  are  massed  in  furrows  they 
may  be  destroyed  by  spraying  them  with  pure  kerosene  or  crude 
petroleum. 

As  in  fighting  chinch-bugs  the  army  worm  must  be  given 
immediate  and  conclusive  combat  if  the  loss  of  crops  is  to  be 
prevented,  for  they  move  rapidly  and  destroy  all  in  their  path. 

The  Fall  Army  Worm  * 

Though  somewhat  the  same  in  its  habits  as  the  true  army 
worm,  the  Fall  Army  Worm  is  so  called  because  it  appears  later 
in  the  season,  the  former  species  being  rarely  injurious  after 
August  1st.  It  is  also  more  omnivorous,  for  while  the  army 
worm  prefers  .grasses,  and  grains,  the  fall  army  worm  feeds 
upon  a  large  variety  of  crops,  including  sugar-beets,  cow-peas, 
millet,  sweet  potatoes,  and  many  other  forage  and  truck  crops. 
In  Nebraska  and  the  Central  West  it  is  a  serious  pest  of  alfalfa 
and  is  called  the  Alfalfa  Worm.  It  is  also  sometimes  very  de- 
structive to  lawns,  as  was  the  case  in  Chicago  in  1S99.  The  fall 
army  Avorm  is  more  of  a  native  of  the  Southern  States,  but 
occurs  from  Canada  to  the  Gulf  and  west  to  the  Rockies. 
*  Laph]jgma  Jnujipcrda  S.  and  A.     Family  Noctuidoc. 


INSECTS  AFFECTING  GRAINS,  GRASSES,  FORAGE         119 


At  first  glance  the  catcrpilhirs  have  niucli  tlie  same  general 
appearance  as  the  army  worm,  but  closer  examination  reveals 
marked  differences.  Along  each  side  of  the  body  is  a  longitudinal 
pitch-colored  stripe,  and  along  the  middle  is  a  yellowish-gray 
stripe  about  twice  as  wide,  which  includes  four  black  dots  on 
each  segment.  The  caterpillars  assume  the  habit  of  working 
in  armies,  but  usually  do  not  feed  in  such  large  numbers  as  the 
tme  army  worms  and  thus  are  more  difficult  to  combat. 

Life  History. — The  winter  is  passed  in  the  pupal  state,  the 
pupffi  being  about  one-half 
inch  long  and  being  found 
in  cells  one-quarter  to  one- 
half  an  inch  below  the  sur- 
face. The  moths  emerge 
in  the  spring  and  the 
females  lay  their  eggs  on 
grass  in  clusters  of  fifty  or 
more,  each  mass  being 
covered  with  the  mouse- 
colored  hairs  from  the  body 
of  the  female.  The  eggs 
hatch  in  about  ten  days 
and  the  caterpillars  are 
found  during  May  and 
June.  The  complete  life 
history  of  the  insect  has 
not  been  carefully  followed, 
but  it  seems  probable  that 
there  are  but  two  complete  generations  in  the  North,  three  gen- 
erations in  the  latitude  of  central  and  southern  Illinois  and  the 
District  of  Columbia,  and  four  in  the  extreme  South.  In  any 
event,  the  destructive  brood  of  caterpillars  appears  in  xVugust  and 
early  September. 

The  parent  moth  is  of  a  "  general  yellowish,  ash-gray  color, 
with  the  second  pair  of  wings  almost  transparent,  but  with  a 
purplish  reflection.       In  extent  of  wings  it  measures  about  l\ 


Fig.  88. — The  fall  army-worm:  a,  moth, 
plain  gray  form;  h,  fore  wing  of  Pro- 
denia-like  form;  c,  larva  extended;  d, 
abdominal  segment  of  larva,  side  view; 
e,  pupa;  d,  twice  natural  size,  others 
enlarged  one-fourth.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 


120         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

inches,  and  when  closed  the  length  of  the  insect  is  about  three- 
quarters  of  an  inch.  The  front  wings  are  mottled  or  marbled, 
especially  near  the  central  area,  and  usually  there  is  visible 
a  fine  white  line  a  short  distance  from  the  edge  and  parallel 
to  it.  The  hind-wings  have  a  fringe  of  darker  hair  as  well 
as  veins  that  contrast  somewhat  with  the  lighter  portion " 
(Fig.  88). 

Control. — Deep  fall  plowing  and  thorough  harrowung  will 
break  up  the  pupal  cells  and  thus  largely  prevent  the  develop- 
ment of  the  spring  brood  of  moths.  In  perennial  crops  like 
alfalfa  thorough  disking  may  be  used  and  on  lawns  deep  raking 
with  a  long-toothed  steel  rake  will  kill  many  of  the  pupa?.  In 
fields  of  young  grain  and  on  lawns  many  of  the  caterpillars  may 
be  killed  by  a  heavy  roller.  When  not  present  in  too  large 
numbers,  the  worms  may  be  destroyed  by  spraying  the  food 
plants  with  Paris  green,  arsenate  of  lead  or  other  arsenicals, 
or  by  the  use  of  poisoned  bran  mash.  When  present  in  large 
numbers  and  the  army  hal^it  is  assumed  they  should  be  cofh- 
bated  the  same  as  the  army  worm. 


CHAPTER  VIII 

INSECTS  INJURIOUS  TO  SMALL  GRAINS  * 

Meadow-maggots  or  Leather- jackets  f 

Several  instances  have  been  recorded  in  which  serious  injury 
has  been  done  to  wheat,  clover,  timothy,  and  blue  grass  by 
the  larvffi  of  Crane-flies.  These  insects  are  never  so  injurious 
in  this  country  as  in  Europe,  where  they  are  known  as  "  daddy- 
long-legs,"  the  common  name  of  our  harvest-spiders,  though 
doubtless  injury  done  by  them  is  often  attributed  to  other  insects. 
The  farmer  usually  declares  the  work  to  be  that  of  wireworms 
or  cutworms,  the  adults  often  being  known  as  "  cutworm-flies," 
unless  the  maggots  are  so  abundant  as  to  attract  his  attention. 
When  the  maggots  are  abundant  enough  to  do  much  injury, 
they  usually  occur  in  very  large  numbers,  but  ordinarily,  though 
common  everywhere,  they  are  not  numerous  enough  to  attract 
attention. 

Several  species  (Tipula  bicornis  Loew,  T.  costalis  Say,  and 
Pachyrrhinis  sp.?)  have  at  various  times  done  considerable 
damage  in  localities  in  Ohio,  Indiana,  Illinois,  and  elsewhere. 

Life  History  — So  far  as  studied,  the  life  histories  of  these 
species  seem  to  be  much  the  same.  The  larvse  remain  dormant 
over  winter,  but  evidently  commence  feeding  again  very  early 
in  the  spring,  a  wheat-field  having  shown  the  effects  of  their 
injuries  from  February  1st  to  April  Lst.  The  larvse  become 
full  grown  from  the  latter  part  of  April  until  the  middle  of  May, 
depending  upon  the  species  and  season.  The  full-grown  maggots 
are  about  an  inch  long,  of  a  dirty-grayish  color,  and  of  a  tough, 

*  See  "  The  Principal  Insect  Enemies  of  Growing  Wheat,"  C.  L.  Marlatt, 
Farmers'  Bulletin  No.  132,  U.  S.  Department  of  Agriculture. 
t  Family  Tipulidce. 

121 


122       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


leathery  texture.  They  are  nearly  cylindrical,  somewhat  taper- 
ing in  front  and  terminating  bluntly  behind.  Legs  are  entircl}^ 
wanting,  but  at  the  blunt  end  are  a  few  fleshy  processes  and  a 
pair  of  small,  horny  hooks.  The  larva  seem  to  prefer  low,  moist 
ground,  and  will  live  for  some  time  on  land  entirely  flooded  or 
in  a  ditch.      They  feed  very  largely  on  dead  vegetable  matter, 

but  when  exces- 
sively abundant 
they  attack  the  roots 
of  wheat,  grass,  and 
clover,  so  weaken- 
ing them  near  the 
surface  that  the 
plants,  deprived  of 
p  rope  r  nourish- 
ment, are  killed  and 
loosened  from  the 
ground. 

Pupse  may  be 
found  during  the 
4atter  part  of  May, 
occupying  small 
cells  in  a  vertical 
position  near  the 
surface  of  the  soil. 
Prior  to  emerging 
the  adult  pushes 
from  one-half  to 
two-thirds  of  the 
Ijody  above  the  sur- 
face and  reniains  in  this  pose  for  several  hours.  The  males 
usually  emerge  first,  as  their  assistance  is  required  by  the 
females,  which  are  loaded  down  with  eggs,  to  extricate  them- 
selves from  the  pupal  skins.  The  sexes  pair  immediately,  there 
being  many  more  males  than  females — one  observer  states  one 
hundred  to  one — and  the  females  deposit  their  eggs  upon  grass 


Fig.  89. 


\   Crane-fly    (Tipula   hebes  Loew):  male 
adult.     (After  Weed.) 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  123 

and  clover  lands,  to  the  number  of  three  hundied  each.  Eggs 
are  laid  for  another  l)rood  in  September,  the  maggots  from  which 
live  over  winter. 

Remedies. — Injury  to  wheat-land  may  be  large!}-  prevented 
by  plowing  earh"  in  September. 

No  satisfactory  remedy  for  the  maggots  is  known  when 
injuring  clover,  timothy,  or  grass,  although  large  numbers  have 
been  destroyed  b}-  driving  a  flock  of  sheep  over  infested 
land.  Dr.  S.  A.  Forbes  states  that  "  close  trampling  of  the 
earth  b}'  the  slow  passage  of  a  drove  of  pigs  would  doubtless 
answer  the -same  purpose,  which  is  that  of  destroying  the  larva? 
lying  free  upon  the  surface  or  barely  embetlded  among  the  roots 
of  the  grass." 

Several  of  our  common  birds  as  well  as  a  number  of  ground- 
beetles  feed  upon  the  maggots  and  flies.  The  maggots  are 
also  sometimes  attacked  by  a  fungous  disease  which  in  the 
damp  soil  in  which  they  live  doul)tless  grows  and  spreads 
rapidly.  Altogether  these  different  enemies  keep  them  so  well 
in  check  that  they  rarely  become  of  importance. 

The  Hessian  Fly  * 

The  Hessian  fl}'  is  much  the  most  destructive  of  any  of  the 
insects  attacking  wheat,  to  which  its  injury  is  practically  con- 
fined; for  though  it  occasionalh'  injures  barley  and  rye,  it  has 
never  been  reared  on  other  grains  or  grasses.  Its  name  was  re- 
ceived from  the  fact  that  it  was  first  noticed  on  Long  Island  in 
1779,  near  where  the  Hessian  troops  had  landed  three  years  before. 
It  now  occurs  over  the  main  wheat-growing  area  of  the  eastern 
United  States  between  parallels  35°  and  45°  westward  to  the  100th 
meridian,  on  the  Pacific  coast,  in  Canada,  and  in  many  other  parts 
of  the  world  where  wheat  is  grown.  Xot  infrequently  it  destroys 
25  to  50  per  cent  of  the  whole  crop  in  some  localities,  and  it  has 
been  estimated  that  10  per  cent  of  the  crop  of  the  whole  couiitry 
is  lost  from  its  ravages. 

Life  History. — The  adult  flies  are  little  dark-colored  gnats  about 
*  Mayetiola  destructor  Say.     Family  Cecidomyidoe. 


124       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


one-tenth  inch  long,  so  small  as  to  commonly  escape  observation. 
Each  female  lays  100  to  150  minute  reddish  eggs,  one-fifteenth 
inch  long,  placing  them  in  irregular  rows  of  from  three  to  five  or 
more,  usually  upon  the  upper  surface  of  the  leaves.  In  a  few  days 
these  hatch  into  small,  ^-eddish  maggots,  which  soon  turn  white, 
are  cylindrical,  about  twice  as  long  as  broad  and  have  no  true  head 
or  legs.  The  fall  brood  of  maggots  burrow  beneath  the  sheaf  of 
the  leaf  and  its  base,  causing  a  slight  enlargment  at  the  point  of 


Fig.  90. — ^The  Hessian  fly  {Mayetiola  destructor):  a.  female  fly;  b,  flaxseed 
stage  or  pupa;  c,  larva;  d,  head  and  breast-bone  of  same;  e,  pupa; 
/,  puparium;  g-,  infested  wheat-stem  showing  emergence  of  pupce  and 
adults.     (After  Marlatt,,  U.  S.  Dept.  Agr.) 

attack;  but  in  the  spring  they  usually  stop  at  one  of  the  lower 
joints,  in  both  instances  becoming  fixed  in  the  plant,  absorbing 
its  sap  and  destroying  the  tissues.  The  first  indications  of  the 
work  of  the  maggots  on  winter  wheat  in  the  fall  are  the  tendency 
of  the  plants  to  stool  out,  the  dark  color  of  the  leaves,  and  the 
absence  of  the  central  stems.  Later  many  of  the  plants  yellow 
and  die.  The  spring  maggots  attack  the  laterals,  or  tillers,  which 
have  escaped  the  previous  brood,  so  weakening  them  that  the 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


125 


stems  break  and  fall  before  ripening  anil  cannot  l)e  readily  hai'- 
vested. 

Al)out  four  weeks  after  hatching  the  maggots  are  full  grown, 
and  arc  greenish-white  and  aliout  three-sixteenths  inch  long.  The 
skin  then  turns  brown,  shrivels  slighth',  and  inside  it  is  formed  the 
pupa.  This  outside  case,  composed  of  the  cast  larval  skin,  is  known 
as  the  "  puparium,"  and  this  stage  is  commonl}^  called  the  "flax- 
seed "  from  the  resemblance  to  that  seed.  In  this  stage  most  of 
the  fall  brood  passes  the  winter,  the  fli<'s  emerging  in  A\)Yi\  or  May, 
while  the  summer 
brood  remains  in 
the  "flaxseed"  stage 
in  the  stubble  dur- 
ing the  late  sum- 
mer and  emerges 
when  the  first  wheat 
is  planted  in  the 
fall,  emerging  later 
further  south. 

Several  species 
of  small  chalcis  flies 
(page  19)  parasitize 
thelarvieand  pupae, 
and  were  it  not  for 
their  assistance  it 
would  doubtless  be 
difficult  to  raise 
wheat.  As  yet  no 
practical  method 
of  increasing  their  al^undance  has  been  devised,  though  colonies 
have  been  carried  to  regions  where  they  were  scarce. 

Control. — The  principal  means  of  avoiding  injury  by  the  Hes- 
sian fly  in  the  winter  wheat  regions  is  late  planting  in  the  fall. 
Inasmuch  as  the  flies  appear  within  aljout  a  week  and  then  dis- 
appear, if  planting  be  delayed  until  after  that  time,  but  little  of  the 
wheat  will  be  injured.     Dry  weather  in  late  summer  and  early 


Fig.   9L — The    Hessian    fly,    adult    male — greatly 
enlarged-.     (After  Marlatt,  U.  S.  D.  Agr.) 


126      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

fall  will  delay  the  appoarance  of  the  flies,  even  with  normal  tem- 
perature conditions,  and  the  further  south,  the  later  they  appear. 
From  experiments  being  conducted  by  the  U.  S.  Bureau  of  Ento- 
mology, Professor  F.  M.Webster  states  that  the  following  dates  will 
probably  be  found  safe  for  sowing  wheat  in  average  seasons:    in 


Fig.  92. — "Flax-seeds"  or  puparia  of  the  Hessian  fly  on  young  wheat — 
enlarged.     (After  Pettit.) 

northern  Michigan  soon  after  the  1st  of  September;  in  southern 
Michigan  and  northern  Ohio,  about  September  20th;  in  southern 
Ohio  after  the  first  week  in  October;  in  Kentucky  and  Tennessee, 
October  10th  to  20th;    in  Georgia  and  South  Carolina,  October 


INSECTS  INJURIOUS   TO  SMALL  GRAINS 


127 


25th  to  November  15th.  The  exact  time  will  also  depend  upon 
altitude  as  well  as  latitude. 

A  rotation  of  the  wheat  crop  compels  the  flies  when  they  emerge 
from  the  stubble  to  travel  in  search  of  the  young  wheat  plants. 
Should  storms  or  heavy  winds  occur,  the  frail  little  flies  will  be  de- 
stroyed in  large  numbers,  whereas  if  they  found  wheat  immedi- 
ately available  the  mortality  would  be  small. 

Inasmuch  as  most  of  the  spring  Ijrood  remain  in  the  stubble 
in  the  flaxseed,  stage  after  harvest,  if  the  fields  be  then  burned 
over,  large  numbers  will  be  destroj'ed.     This  may  be  done  by  cut- 


A 


A 


P'iG.  93. — Hessian  fly:  o,  egg,  greatly  enlarged;  6,  section  of  wheat-leaf 
showing  eggs  as  usually  deposited — less  enlarged;  c,  larva;  d,  pupa 
taken  from  puparium  or  "flaxseed" — e;  c,  d,  e,  much  enlarged.  (After 
Webster  and  Marlatt,  U.  S.  Dept.  Agr.) 


ting  the  grain  rather  high  at  harvest,  and  then  mowing  the  weeds 
and  grass  and  allowing  them  to  dry  a  few  days  Ijefore  burning. 
Unfortunately  this  practice  is  often  impossible,  owing  to  the  prac- 
tice of  seeding  wheat  land  to  grass  and  clover. 

As  early  volunteer  plants  always  become  badly  infested  and  the 
pupae  wintering  on  them  give  rise  to  a  spring  brood  which  attacks 
the  main  crop,  all  volunteer  plants  should  l)e  destroyed  by  plowing 
or  disking  before  the  larva  have  matured.  This  principle  has  some- 
times been  utilized  in  the  form  of  a  trap  crop,  strips  of  wheat  being 
sown  early  so  as  to  attract  the  flies  and  then  being  plowed  under 


128         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

after  the  bulk  of  the  eggs  had  been  laid  upon  them,  thus  protecting 
the  main  crop,  planted  later. 

The  enrichment  of  the  soil,  the' preparation  of  a  good  seed  bed, 
and  the  use  of  good  seed,  so  as  to  secure  a  vigorous  growing  crop, 
are  all  of  the  greatest  importance  in  overcoming  injury  by  the 
Hessian  fly.  After  the  crop  is  once  attacked,  no  truly  remedial 
measures  arc  known  except  to  appl}'  liberally  some  quick-acting 
fertilizer  which  will  cause  the  plants  to  tiller  freely  and  give  them 
sufficient  vigor  to  withstand  the  winter  and  thus  increase  the 
healthy  stems  the  next  spring. 

Though  none  are  exempt  from  attack,  those  varieties  of  wheat 
"  with  large,  coarse,  strong  straw  are  less  liable  to  injury  than 
weak-strawed  and  slow-growing  varieties."  *  In  New  York  in 
man}'  localities  in  1901  a  wheat  called  Dawson's  Golden  Chaff  was 
found  to  be  but  little  injured,  where  others  were  nearly  destroyed. 
However,  in  Canada,  where  this  variety  originated,  it  is  as  seriously 
injured  as  other  kinds,  and  may  become  so  in  New  York.  Bearded 
Red  Wheat  No.  S  was  also  found  to  be  a  very  resistant  variety,  as 
were  Prosperity,  Democrat,  Red  Russian,  and  White  Chaff  Medi- 
terranean. It  should  be  remembered,  however,  that  none  of 
these  are  invariably  "  fly-proof,"  and  that  though  under  certain 
conditions  they  may  be  but  little  injured,  in  other  localities  and 
under  less  favorable  circumstances  the}^  may  be  injured  as  much 
as  any  other  sorts. 

Among  other  conclusions  Professor  Roberts*  and  his  colleagues 
state  that  the  fly  "  injures  wheat  more  on  dryish  and  poor  land 
than  on  moist  but  well-drained,  rich  soils."  Also,  "  that  the  soil 
must  be  so  well  fitted  and  so  fertile  that  a  strong,  healthy  growth 
will  be  secured  in  the  fall,  though  the  sowing  of  the  seed  be  delayed 
ten  to  fifteen  days  beyond  the  usual  time.  Such  preparation  of 
the  soil  will  also  help  the  wheat  to  recover  from  any  winter  injury. 
Thick  seeding  and  vigorous  growth  also  tend  to  ward  off  the  fly." 
"  Much  stress  should  be  laid  on  the  proper  fitting  of  the  land  for 
wheat.     Plowing  should  he  done  early — at  least  six  weeks  before 

*  Cornell  University  Agr.  Exp.  Sta.,  Bulletin  194:  The  Hessian  Fly,  I.  P. 
Roberts,  M.  V.  Slingcrland,  and  J.  L.  Stone. 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  129 

sowing — to  give  abuiicUmt  time  for  the  repeated  working  of  tlic 
soil  in  order  to  recompact  the  subsurface  soil  and  secure  a  fine  but 
shallow  seed-bed  in  which  there  has  been  developed,  by  tillage  and 
the  action  of  the  atmosphere,  an  abundance  of  readily  available 
plant  food.  Manures  and  fertilizers  should  be  kept  near  the  sur- 
face and  the  young  roots  encouraged  to  spread  out  on  the  surface 
soil,  thus  avoiding  much  of  the  damage  by  heaving  in  winter  and 
leaving  the  deeper  soil  for  fresh  pasturage  for  the  plants  during 
the  following  spring  and  summer." 

In  summarizing  his  knowledge  of  means  of  controlling  this 
pest,  Professor  F.  M.  Webster,  who  is  probably  our  best  authority 
upon  it  ,says:  "  After  thirteen  years  of  study  of  the  Hessian  fly, 
I  am  satisfied  that  four-fifths  of  its  injuries  may  he  prevented  by 
a  better  system  of  agriculture.  For  years  I  have  seen  wheat  grown 
on  one  side  of  a  division-fence  without  the  loss  of  a  bushel  by 
attack  of  this  pest,  while  on  the  other  side  the  crop  was  invariably 
always  more  or  less  injured.  No  effect  of  climate,  meteorological 
conditions,  or  natural  enemies  could  have  brought  about  such  a 
contrast  of  results.  The  whole  secret  was  in  the  management 
of  the  soil  and  the  seeding." 

The  Wheat  Saw-fly  Borer  * 

The  "Corn  Saw-fly"  has  for  many  years  been  a  well-known 
wheat  pest  throughout  England,  France,  and  the  Continent, 
but  was  not  noted  as  injurious  in  this  country  till  1889,  w^hen 
Professor  J.  H.  Comstock  published  a  very  complete  account 
of  its  injuries  upon  the  University  Farm  at  Ithaca,  N.  Y.,  where 
it  had  done  more  or  less  damage  for  two  3'ears,  though  Mr. 
F.  H.  Chittenden  states  that  he  collected  a  single  adult  at  Ithaca 
in  the  early  '80's.  Specimens  were  also  collected  at  Ottawa, 
Canada,  and  Buffalo,  N.  Y.,  in  1887  and  1888,  and  injury  has  been 
reported  by  Dr.  James  Fletcher  from  Manitoba  and  the  Northwest 
Territories.  The  injury  under  Dr.  Fletcher's  observation,  how- 
ever, was  probabl}^  due  to  a  nearly  related  species,  the  Western 

*  Cephus  pygmceiis  Linn.     Family  Cephidce.      Bulletin  11,  Cornell  Univ 
Agr.  Exp.  Station. 


130        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Injury. 


Grass-stem  Saw-fly  (Cephas  occidenlalis  lliley  and  Marlatt). 
This  is  a  native  species  which  normally  lives  in  wild  grasses  and 
which  has  been  quite  injurious  in  certain  sections  of  the  North- 
west during  recent  years.  It  hal)its  and  the  means  of  control 
are  practically  identical  with  the  species  here  discussed.! 

The  following  is  gleaned  from  Professor  Comstock's  interesting 
account. 

No  external  indications  of  injury  to  the  plant  can 
be  seen  until  the  larva  within 
has  almost  completely  tunneled 
the  stalk,  at  which  time  there 
is  a  discoloration  just  below  the 
injured  joints.  Thus  damage  by 
this  insect  is  not  readily  noticed, 
it  merely  dwarfing  and  stunting 
the  growth  of  the  plant  by  bor- 
ing in  the  stem. 

"  If  infested  straws  be  ex- 
amined a  week  or  ten  days  before 
the  ripening  of  the  wheat,  the 
cause  of  this  injury  can  be  found 
at  work  within  them.  It  is  at 
that  time  a  yellowish,  milky- 
white  worm,  varying  in  size  from 
one-fifth  to  one-half  an  inch  in 
length.  The  smaller  ones  may 
not  have  bored  through  a  single 
joint;  while  the  larger  ones  will 
have  tunneled  all  of  them,  except, 
perhaps,  the  one  next  to  the  ground. 

Life  History. — "  As  the  grain  becomes  ripe  the  larva  works 
its  way  toward  the  ground ;  and  at  the  time  of  harvest  the  greater 
number  of  them  have  penetrated  the  root.  Here,  in  the  lowest 
part  of  the  cavity  of  the  straw,  they  make  preparations  for  pass- 
ing the  winter,  and  even  for  their  escape  from  the  straw  the 
t  See  F.  M.  Webster,  Circular  117,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


Fig.  94. — The  wheat  saw-fly  liorer 
(Cephus  pygmceus  Linn.):  a,  ou'- 
hne  of  larva,  natural  size;  b,  larva, 
enlarged ;  c,  larva  in  wheat-stalky 
natural  size;  d,  frass;  e,  adult 
female;/,  Pachyonerus  calcitrator , 
female,  a  parasite  —  enlarged. 
(After  Curtis,  from  "Insect  Life.") 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  131 

following  year.  Tliis  is  done  by  cutting  the  straw  circularly 
on  the  inside,  nearl}-  severing  it  a  short  distance,  varying  from 
one-half  to  one-inch,  from  the  ground.  If  the  wheat  Were  grow- 
ing wild,  the  wint(n-  winds  would  cause  the  stalk  to  l)reak  at 
this  point;  and  thus  the  insect  after  it  had  reached  the  adult 
state  couhl  easily  escape;  while  but  for  this  cut  it  would  be  very, 
liable  to  be  imprisoned  in  the  straw."  OrcUnarily,  the  straw  is 
cut  by  the  reaper  before  it  becomes  broken;    but  a  strong  wind 


Fig.  95. — The  western  grass-stem  saw-flj^  (Ccphun  occidental i s) :  a,  larva; 
b,  female  saw-fly;  c,  grass-stem  showing  work,  c,  enlarged,  a,  b,  more 
enlarged.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

just  before  harvest  Avill  cause  a  large  number  of  stalks  to  become 
broken,  much  as  if  affected  by  the  Hessian  fly. 

"  After  the  circidar  cut  has  been  made,  the  larva  fills  the 
cavity  of  the  straw  just  below  it  for  a  short  distance  with  a  plug 
of  borings.  Between  this  plug  and  the  lower  end  of  the  cavity 
of  the  straw  there  is  a  place  about  one-half  an  inch  in  length. 
It  is  here  that  the  insect  passes  the  winter."  This  cell  is  lined 
with  silk  so  as  to  form  a  warm  cocoon.  Here  the  larva  passes 
the  winter  and  changes  to  a  pupa  in  March  or  April.  The  adult 
insect  emerges  early  in  May.     The  adults  are  four-winged  insects, 


132       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

and  are  popularly  known  as  saw-flies  on  account  of  the  saw-like 
ovipositor  of  the  female,  by  means  of  which  she  inserts  her 
eggs  in  the  tissue  of  the  plant.  This  species  is  quite  different  in 
some  respects  from  the  saw-flies  feeding  upon  the  leaves  of  wheat, 
and  belongs  to  the  family  Cephidce. 

The  female  commences  to  lay  eggs  by  the  middle  of  May. 
By  means  of  her  sharp  ovipositor  she  makes  a  very  small  slit 
any  place  in  the  stalk  of  the  plant  and  in  this  thrusts  a  small 
white  egg — about  Vioo  of  an  inch  long — which  is  pushed  clear 
through  the  walls  of  the  straw  and  left  adhering  to  the  inside. 
Though  several  eggs  are  deposited  in  a  straw,  but  one  larva 
usually  develops.  "  The  eggs  hatch  soon  after  they  are  laid, 
and  the  larvae  may  develop  quite  rapidly.  A  larva  which 
hatched  from  an  egg  laid  May  13th  was  found  t-o  have 
tunneled  the  entire  length  of  the  stalk  in  v/hich  it  was  "  on  May 
28th. 

Remedies.—"  The  most  obvious  method  of  combating  the 
insect  is  to  attack  it  while  it  is  in  the  stubble;  that  is,  sometime 
between  harvest  and  the  following  May.  If  the  stubble  can  be 
burned  in  the  autumn,  the  larva3  in  it  can  be  destroyed.  The 
same  thing  could  be  accomplished  by  plowing  the  stubble  under, 
which  would  prevent  the  escape  of  the  adult  flies.  But  as  it  is 
(often)  customary  ...  to  sow  grass-seed  with  wheat,  it  is  feared 
that  the  plowing  under  of  infested  stubble  would  rarely  be  prac- 
ticable; and  it  is  also  questionable  if  the  burning  of  the  stubble 
could  be  thoroughly  done  without  destroying  the  young  grass. 
It  would  seem  probable,  therefore,  that  if  this  insect  becomes 
a  very  serious  pest,  it  will  be  necessary.  .  .  either  to  sow  grass- 
seed  with  oats  and  burn  or  plow  under  all  the  wheat  stubble, 
or  to  suspend  growing  wheat  for  one  year,  in  order  to  destroy 
the  insects  by  starvation." 

Some  Wheat-maggots 

Very  similar  to  the  Hessian  fly  in  its  mode  of  injuring  the 
wheat-stalk  is  the  Wheat-stem  Maggot  {Meromyza  americana 
Fitch).    The  adult  flies  were  first  described  by  Dr.  Fitch  in  1858, 


INSECTS   INJURIOUS   TO  SMALL  GRAINS 


133 


though  the  work  of  the  maggots  had  probably  been  noticed  as 
early  as  1821  by  James  Worth  of  Bucks  County,  Pa.,  and  by  the 
Michigan  Farmer  in  Michigan  about  1845. 

Extending  from  Dakota  and  Manitol)a  to  Texas,  the  range 
of  this  insect  practically  covers  all  the  eastern  United  States  and 
southern  Canada. 

Unlike  the  Hessian  fly  it  feeds  and  brectls  upon  wild  grasses  and 
is  thus  much  more  difficult  to  control.  Prof.  A.  J.  Cook  found 
the  larvffi  in  both 
barley  and  oats  in 
Michigan,  Prof.  F. 
M.  Webster  reared 
an  adult  from  blue 
grass  {Poa  praten- 
sis),  and  Dr.  Jas. 
Fletcher  records  it 
as  breeding  in 
Agropi/noii,  Des- 
champsis,  Ehjmus, 
Poa,  and  Setaria 
viridis    in  Canada. 

Life  Histori/. — 
Like  the  Hessian 
fly  the  adult  flies 
lay  their  eggs  on 
fall  wheat  in  Sep- 
tember and  Octo- 
ber, and  the  young  maggots  when  hatched  work  their  way 
down  into  the  stem,  either  cutting  it  off  or  causing  it  to  discolor 
or  die.  The  eggs  are  about  one-fortieth  of  an  inch  long  and 
of  a  glistening  white  color.  The  larvae  are  a  light  greenish 
color,  about  one-fourth  of  an  inch  long,  tapering  toward  the 
terminal  end  while  subcylindrical  posteriorly,  being  quite  elon- 
gate. The  pupie  are  the  same  color  as  the  larva?,  but  more 
rounded,  being  only  one-sixth  of  an  inch  long,  and  reveal  the 
legs  and  wing-cases  of  the  imago  forming  within  them.     The 


Fig.  96. — Wheat  bulb-worm  {Meromyza  americana): 
a.  mature  fly;  6,  larva;  c,  puparium;  d,  infested 
wheat-stem — all  enlarged  except  d.  (After 
Marlatt,  U.  S.  Dept.  Agr.) 


134       INSECT   PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


external  case  of  the  pupa,  called  the  puparium,  is  merely  the 
shrunken  and  hardened  cast  skin  of  the  last  larval  stage, 
within  which  the  insect  transforms  to  the  pupa.  The  fly  is 
about  one-fifth  of  an  inch  long.  It  is  of  a  yellowish-white 
color  with  a  black  spot  on  the  top  of  the  head,  three  broad  black 
stripes  on  the  thorax,  and  three  on  the  abdomen,  which  are  often 
interrupted  at  the    sutures,    so   that   they   form    distinct  spots. 

The  eyes  are  a  bright 
green. 

The  winter  is  passed 
by  the  larvai  in  the 
young  plants  and  in 
spring  they  transform 
to  pupae  and  adult 
flies.  These  in  turn 
deposit  eggs  in  such  a 
position  that  the  mag- 
gots issuing  from  them 
may  readily  feed  upon 
the  succulent  portions 
of  the  growing  stalk. 
Numerous  larvse  thus 
sapping  the  life  of  the 
plant  soon  kill  it  out- 
right or  cause  the  top 
and  head  to  wither  and 
die.  The  adults  of  this  brood  emerge  in  July  and  lay  eggs 
on  volunteer  wheat  and  grasses,  the  maggots  working  in  the 
same  manner  as  in  the  fall  and  coming  to  maturity  so  that 
another  brood  of  flies  lays  eggs  for  the  fall  brood  on  the  newly 
planted  wheat. 

Owing  to  the  fact  that  this  insect  breeds  also  in  grasses  dur- 
ing late  summer  it  is  much  more  difficult  to  combat  than  were  it 
confined  to  wheat  as  its  food-plant,  as  is  the  Hessian  fly. 

Remedies. — ''  If  the  grain  is  stacked  or  threshed  and  the 
straw  stacked  or  burned,"  says  Professor  Webster,  "  it  is  clear  that 


Fig.  97. — The  American  frit-fly  (Oscinin  variabilis 
Loew):  a,  larva  or  maggot;  b,  puparium;  c, 
adult  fly.     (After  Garman.) 


INSECTS    INJURIOUS   TO  SMALL   GRAINS  135 

the  number  escaping  would  be  greatly  reduced,"  for,  as  the 
adults  emerge  soon  after  harvest,  they  would  escape  to  deposit 
their  eggs  were  the  straw  left  in  the  fields,  but  "it  is  not  likely 
that  those  in  the  centre  of  the  stacks  would  be  able  to  make 
their  wa}'  out,  and  the  threshing-machine  would  destroy  many 
more.  How  much  could  be  accomplished  l)y  late  sowing  of  grain 
is  uncertain,  as  the  females  are  known  to  occur  abundantly  up  to 
October.  If  plots  of  grain  were  sowed  immediately  after  harvest 
in  the  vicinty  of  the  stacks,  many  of  the  females  could,  no  doubt, 
be  induced  to  deposit  their  eggs  therein,  and  these  could  be 
destroyed  by  plowing  under."  Burning  of  the  stubljle  will  also 
aid  in  keeping  this  pest  under  control. 

There  are  several  undetermined  species  of  flies  belonging 
to  the  genus  Oscinis,  which  have  practically  the  same  life  history 
as  the  wheat  stem-maggot  and  injure  the  wheat  in  the  same 
manner.  They  very  closely  resemble  the  common  house-fly  in 
miniature,  being  about  one-fourth  as  large.  They  will  not  need 
consideration  by  the  practical  farmer  other  than  in  applying 
methods  of  control  as  already  given.  One  species  of  this  genus, 
determined  by  Professor  H.  Garman  as  Oscinis  variabilis  Loew  and 
christened  the  American  Frit-fly,  has  been  found  common  in 
Kentucky  antl  Canada,  but  in  the  larval  stage  is  so  nearly 
identical  in  appearance  and  habit  with  the  stem-maggot  that  it 
can  with  diTiculty  be  distinguished  from  it. 

That  these  pests  do  not  do  more  injury  is  probably  due,  to  a 
considerable  extent,  to  the  fact  that  large  numbers  of  them  are 
destro3'ed  by  a  small  hymenopterous  parasite,  known  as  Coelinus 
meromyza:  Forbes,  w^hich  very  commonly  infests  the  larvae,  and 
by  other  parasites  and  preclaceous  insects. 

Rarely  will  these  pests  do  serious  damage,  but  very  often 
it  is  sufficient  to  merit  consideration,  and  only  a  knowledge  of 
their  life  history  can  give  a  key  to  their  successful  control. 


130        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Wheat  Joint-worm  * 

For  the  last  sixty  years  the  joint-worm  has  been  known  as 
a  serious  pest  of  wheat  throughout  the  wheat-growing  region 
east  of  the  Mississippi  River,  the  damage  varying  from  a 
slight  injury  which  is  hardly  noticeable,  and  which  may  escape 
observation  for  several  years,  to  an  almost  total  destruction  of 
the  crop. 

The  adults  appear  in  April,  May,  or  early  June,  according  to  the 
latitude,  and  are  small  black,  four-winged  flies  about  one-eighth 
inch  long,  with  the  joints  of  the  legs  and  feet  yellow.     They  look 

s  o  m  e  t  h  i  n  g  like 
small,  winged  black 
ants  (Fig.  99)  and 
curiously  enough 
belong  to  a  family 
whose  members  are 
almost  all  parasitic 
on  other  insects,  so 
that  before  they  had 
been  thoroughly 
studied  they  v/ere 
thought  to  be  para- 
sites of  the  Hessian 
fly.  The  females 
lay  their  eggs  in  the  stems,  generally  selecting  the  uppermost 
joints  that  have  appeared  at  that  time.  "  The  young  worms 
develop  rapidly,  each  in  a  little  cavity  within  the  straw.  Often 
knots,  swellings,  and  twistings  occur  in  the  straw  at  the  point 
of  infestation;  again  there  is  little  sign  of  the  insect's  presence 
except  a  slight  discoloration  or  a  little  deviation  of  the  fibres 
and  grooves  of  the  straw  from  their  natural  course.  When  the 
infested  section  is  split  with  a  knife  it  is  found  to  be  jjrittle  and 

*  Isosoma  tritici  Fitch.  Family  Chalcididce.  See  J.  S.  Houser,  Bulletin 
226,  Ohio  Agr.  Exp.  Sta.;  and  F.  M.  Webster,  Circular  66,  Bureau  of  Ento- 
mology, U.  S.  Dept.  Agr. 


Fig.  98. — a,  wheat-straw  affected  by  joint-worm;  b, 
adult  as  seen  from  above.     (After  Riley.) 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


137 


woody  in  character,  and  contains  from  3  or  4  to  20  or  more  yel- 
lowish hirvie,  aljout  one-eighth  inch  long  when  full-grown.  These 
larva;  remain  in  the  straw  until  the  following  spring,  when  they 
issue  as  adults  and  commence  again  the  life  cycle  in  the  new  crop. 
The  damage  is  done  by  the  worms  cutting  off  the  sap  supply 
from  the  head,  causing  it  to  become  shortened,  containing 
comparatively  few  kernels,  and  such  kernels  as  develop  are  apt 
to  be  small  and  shriveled  from  lack  of  nourishment.  Also  because 
of  the  brittleness  of  the  straw  high  winds  are  apt  to  break  much 
of  it  down." — Gossard. 

The  presence  of  the  pest  is  always  indicated  at  threshing  by 


Fig.  99. — Wheat  straw-worm  (Isosoma  gj-andcJiiley):  o,  ventral  view;  6,  side 
view  of  larva;  c,  antenna?;  d,  mandible;  e,  anal  segment,  ventral  view;  /, 
adult  female;  g,  fore-wing;  h,  hind-wing;   i,  aborted  wing.    (After  Riley.) 


short,  hard  bits  of  straw,  containing  the  larva?,  which  are  carried 
out  with  the  grain  instead  of  going  over  in  the  straw.  It  has 
usually  been  considered  necessary  to  separate  and  burn  these, 
Init  Professor  F.  M.  Webster  finds  that  the  larvae  in  them  are 
probably  killed  in  threshing,  as  he  has  been  unable  to  rear 
adults  of  cither  the  joint-worm  or'its  parasites  from  such  bits  of 
straw. 

Control. — A  rotation  of  the  wheat  crop  is  of  primary  impor- 
tance in  the  control  of  this  pest,  and  where  wheat  is  not  planted 
on  the  same  land  and  is  sown  as  far  from  that  of  the  previous 


138       INSECT  PESTS  OP^  FARM,   GARDEN  AND  ORCHARD 

year  as  possible  there  will  be  but  little  damage.  It  is  obvious 
that  the  stubble  should  be  plowed  under  where  possible,  or  burned 
during  the  late  fall  or  winter.  Cut  infested  grain  as  low  as  pos- 
sible so  as  to  remove  the  larvaj  in  the  straw.  Where  the  stubble 
cannot  be  burned,  break  it  down  by  harrowing  in  the  spring  and 
then  collect  with  a  hayrake  and  burn.  Prepare  the  seed  bed 
thoroughly  and  fertilize  well,  when  injury  is  expected,  so  as  to 


Fig.  100. — Swellings  made  by  wheat  joint-worms  in  straw — enlarged.     (After 

Pettit.) 

ensure  a  strong  growth  and  early  ripening.  Green  manure 
containing  infested  straw  should  not  be  scattered  on  land  to  be 
used  for  wheat,  and  all  infested  straw  which  has  not  been  used 
up  by  April  should  hv  Ijurned. 

The  Wheat  Straw-worm  * 


''  The  Wheat  Straw-worm,"  says  Professor  F.  M.Webster,''  sus- 
tains the  same  relation  to  winter-wheat  culture  west  of  the  Miss- 
issippi River  that  the  joint-worm  does  to  the  cultivation  of  this 
cereal  east  of  this  river.  Both,  when  excessively  abundant, 
occasion  losses  from  slight  to  total.  A  wheat  stem  attacked 
by  the  joint-worm  may  produce  grain  of  a  more  or  less  inferior 
quality  and  less  of  it;  but  the  spring  attack  of  the  wheat  straw- 
*  Isosoma  grandc  Riley.     Family  Clialcididw. 


INSECTS   INJURIOUS  TO  SMALL  GRAINS 


139 


worm  is  fatal  to  the  plant  affected,  as  no  grain  at  all  is  produced, 
and  while  the  second  generation  of  the  same  has  a  less  disastrous 
effect  in  the  field,  it  nevertheless  reduces  the  grade  and  weight 
of  the  grain."  Though  the  straw-woi"m  occurs  over  much  of 
the  same  territory  in  the  East  as  the  joint- worm,  it  is  rarely  so 
injurious. 

Life  History  and  Description.'^  "  There  are  two  generations 
of  the  insect  annually,  the  adults  of  the  first  generation  differing 
considerably  in  appearance  from  those  of  the  second.  To  the 
farmer  they  will  all  look  like  minute  or  large,  shining  black  ants, 


I'iG.    lOL — Wheat  straw-worm:    adult  of  fall   generation,   much  enlarged. 
(After  Howard,  U.  S.  Dept.  Agr.) 


with  or  without  wings,  their  legs  more  or  less  banded  with  yellow, 
and  having  red  eyes.  Individuals  of  the  first  generation  emerge 
in  April  from  the  outstanding  straws  and  stubble.  They  are 
very  small,  most  of  them  are  females,  and  many  are  wingless. 
The  females  deposit  their  eggs  in  the  young  wheat  plants,  the 
stems  of  which  at  this  time  extend  but  little  above  the  sur- 
face of  the  ground.  The  egg  is  placed  in  or  just  below  the 
embryonic  wheat  head   and   the   larva  or  worm  works  within 

*  From  Circular  106,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  by  F.  M. 
Webster  and  Geo.  I.  Reeves. 


140       INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


the  stem,  usually  causing  a  slight  enlargement.  When  the 
worm  is  full  grown  it  will  be  found  in  the  crown  of  the"  plant, 
having  eaten  out  and  totally  destroyed  the  embryonic  head, 
its  body  occupying  the  cavity  thus  formed. 

"The  females  which  deposit  these  eggs,  being  small  and  fre- 
quently wingless,  are  in  no  way  fitted  for  traveling  long  dis- 
tances. The  larva  or  worm  is  of  a  very  light  straw  color,  indeed 
almost    whit(\,   with    Ijrown    jaws.     These  worms    develop    very 

rapidly  and;  as  they  feed 
on  the  most  nutritious  part 
of  the  plant,  they  become 
robust  and  larger  than 
those  found  in  the  mature 
straw  in  late  summer.  In 
May  the  larvae  become  full 
grown  and  pass  at  once 
through  a  short  pupal 
stage.  The  pupae  are  at 
first  the  same  color  as  the 
larvae,  but  later  change  to 
a  shining  jet  black.  In 
a  few  days  the  fully  devel- 
oped insects  gnaw  circular 
holes  through  the  walls  of 
the  stem  and  make  their 
way  out.  These  adults  are 
much  larger  and  more  robust  than  the  individuals  of  the  first 
generation  and  are  provided  with  fully  developed,  serviceable  wings. 
That  they  make  good  use  of  their  wings,  and  scatter  themselves 
about  over  fields  adjacent  to  their  place  of  development,  is  shown 
by  their  occurrence  in  fields  of  grasses  (in  the  stems  of  which 
they  do  not  breed)  situated  considerable  distances  from  wheat 
fields.  In  ovipositing,  the  females  of  this  generation  select 
the  largest  and  most  vigorous-growing  stems  in  which  to  place 
their  eggs. 

"  The  adults    of  the  second    generation  deposit   their   eggs 


a 

Fig.  102. — The  wheat  straw-worm: 
method  of  oviposition  of  female  of 
summer  form:  a,  female  inserting 
her  eggs,  h,  section  of  wheat  stem, 
showing  egg;  c,  and  ovipositor,  d; 
c,  egg,  greatly  magnified.  (After 
Riley  and  Webster,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


141 


from  early  Ma}',  in  Texas,  up  to  the  mitldlc  of  June,  in  northern 
Indiana,  or  about  the  time  the  wheat  is  heading.  Their  aim 
at  this  time  is  to  phice  the  eggs  singly  in  the  growing  stem, 
just  above  the  youngest 
and  most  succulent  joints, 
which  are  not  so  covered 
by  the  enfolding  leaf 
sheaths  as  to  be  inaccessi- 
ble to  them.  Thus  it  is 
that  the  stage  of  advance- 
ment in  the  growth  of  the 
wheat  stem  at  the  time  of 
oviposit  ion  of  the  summer 
generation  of  females 
determines  whether  the 
larvie  will  be  well  upward 
in  the  straw,  and  there- 
fore removed  after  har- 
vest, or  lower  down  and 
consequently  left  in  the 
field  in  the  stubble. 

"  The  methotl  of  ovi- 
position  and  the  point 
where  the  egg  is  usually 
formed  is  shown  in  Fig. 
103.  The  larva  forms  no 
gall,  nor  does  it  harden 
the  stem  witiiin  which  it 
develops.  There  is  nor- 
mally but  one  larva  in  each  joint;  but  if  several  eggs  have  been 
placed  between  joints  and  produce  larvse  there  will  be  one  in  the 
centre  of  the  stem  just  above  the  joint  and  others  in  the  walls  just 
under  the  internal  wall-covering  or  inner  epidermis.  These  larvse 
in  the  walls  of  the  straws  do  not,  as  a  rule,  kill  the  stem,  but 
their  effect  is  to  ciutail  the  yield  by  reducing  the  weight.  The 
larva?  develop  rapidly  and   reach  their  full  growth  before  the 


Fig.  103. — Wheat  straw-worm,  sho^ving 
point  where  female  of  the  spring  form 
deposits  the  egg  in  young  wheat  in  early 
spring.  Enlarged  showing  position  of  egg 
at  right.    (After  Wester,  U.  S.  Dept.  Agr.) 


142      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

straw  has  hardened.  By  October^,  in  the  Middle  West,  though 
earlier  in  the  South,  they  pass  into  the  pupal  stage,  in  which,  as  a 
rule,  they  remain  until  early  spring,  whereupon  they  develop  to 
adults  and  gnaw  their  way  out."  In  the  Northwest,  w^here  both 
winter  and  spring  wheat  are  grown,  the  injury  is  particularly 
severe  to  spring  wheat,  as  the  adults  of  the  second  generation  from 
winter  wheat  oviposit  upon  it  while  it  is  still  young  and  ruin  it  in 
much  the  same  way  as  the  first  generation  does  on  the  winter 
wheat  in  spring.  Volunteer  plants  which  carry  the  pest  over 
winter  have  the  same  effect  in  increasing  the  injury  to  spring 
wheat. 

Control. — A  rotation  of  crops  which  will  eliminate  the  growing 
of  wheat  two  years  in  succession  on  the  same  land  is  by  all  means 
the  most  successful  and  practicable  means  of  control.  The  adults 
of  the  first  generation  are  very  small  and  largely  wingless;  they  are 
unable  to  migrate  far,  so  that  rotation  is  exceedingly  efficacious, 
though  it  should  be  planned  so  that  wheat  is  not  planted  next  to 
stubble  land,  for  the  edge  will  become  infested  by  the  first  genera- 
tion, and  the  second  generation  will  then  become  distributed 
throughout  the  field.  The  burning  of  stuljble  and  outstanding 
straw  will  be  advantageous  wherever  practicable.  Clean  fallow- 
ing in  early  summer  and  the  abandonment  of  spring-wheat  culture 
will  reduce  injury  in  the  Northwest. 


Wheat  Saw-flies  * 

Several  species  of  saw-fly  larvsc  sometimes  feed  on  the  leaves 
and  rarely  on  the  heads  of  wheat,  but  seldom  do  serious  injury. 
Dolerus  arvensis  Say  and  Dolerus  coUaris  Say  have  both  been 
reared  upon  wheat  from  Ohio  and  New  Jersey,  though  both  species 
occur  throughout  the  United  States  and  southern  Canada  east  of 
the  Rockies.  The  adult  flies  "  are  comparatively  large,  robust  in- 
sects, of  a  dull  black  or  bluish  color,  varied  with  yellow  or  reddish." 
"  The  larvse  are  quite  uniform  in  color  and  general  characteristics. 
They  have  twenty-two  legs,    are  cj'lindrical,  and  generally  of  a 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  143 

uniform  grayish  or  slaty  color,  dorsally  and  laterally,  but  nearly 
white  ventrally."  * 

The  adults   deposit   their  eggs  in  the  spring,  and  larvaj  are 
to  be  found  early  in  June. 

The  only  record  found  of  the  life  history  is  that  of  D.  collaris 
by  Professor  F.  M.  Webster,  who  found  that  a  larva  collected 
on  June  15,  1897,  entered  the  ground  in  about  ten  days,  and 
the  first  adult  emerged  January-  11,  1S9S,  though  the  adults 
usually  appear  later. 

The  most   common  saw-fly   feeding    upon   wheat   foliage    is 


Fig.   104. — .V  wheat  saw-fly    (Dolerns  arvensis  Say) :   female — much  enlarged. 
(After  Riley  and  Marlatt,  U.  S.  Dept.  Agr.) 

Pachynematus  extensicornis  Norton.  "  The  adult  insects  appear 
during  the  latter  part  of  April  and  first  of  May,  the  males  antedat- 
ing the  females  several  days.  The  eggs,  when  first  laid,  are  of  a 
light  green  color.  They  are  inserted  to  the  number  of  two  to  five, 
or  more,  together  along  the  edges  of  the  wheat-blades  and  just 
beneath  the  epidermis.  Some  fifteen  or  sixteen  days  elapse  before 
hatching.  The  newly  hatched  larva  is  rather  slender  and  elongate, 
tapering  gradually  from  the  head  to  the  last  segment;  head  yel- 
lowish, eyes  black.     Full  growth  is  attained  in  about  five  weeks, 

♦Family    Tenthredinidoe.     AVheat  and   Grass  Saw-flies.     C.  V.  Riley  and 
C.  L.  Marlatt,  "  Insect  Life,"  Vol.  IV,  p.  169. 


144      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  mature  larva  having  a  length  of  about  four-fifths  of  an  inch. 
The  head  is  of  a  pale  clay-yellow  color,  the  c}'es  are  black,  and  the 
color  of  the  body  is  green  or  yellowish  green.  The  larva  is  at  once 
separated  from  the  Dolerus  larvse  by  the  possession  of  but  seven 
pairs  of  abdominal  feet."  (R.  and  M.,  I.e.)  When  full-grown  the 
larvae  enter  the  earth  and  construct  silken  cocoons,  in  which  they 


Fig.  105. — The  grass  saw-fly  {Pacliynematus  extensicornin  Norton) :  a,  a,  eggs 
on  wheat-blade;  young  larva";  c,  full-grown  larva;  d,  cocoon  from 
which  adult  has  emerged;  e, /,  adult  insects — c,  male;  /,  female,  a  and 
h,  naturalsize;  c-/,  enlarged,     (.\fter  Riley  and  Marlatt,  U.  8.  D.  Agr.) 


doubtless  remain  unchanged  over  winter,  transforming  to  pupae 
shortly  l^efore  the  adults  emerge  the  next  spring.  The  form  of  the 
adults  is  well  shown  in  the  illustration.  ''  The  female  is  stout  and 
in  general  light  yellowish  or  ochi-aceous  in  color.  The  abdomen 
is  for  the  most  part  daik  bi'own  oi'  black,  doi'sally,  except  the  pos- 
terior lateral  nuirgin  and  the  extreme  tip.  The  male  is  much  more 
slender  and  elongate  than  the  female,  and  is  almost  black  in  color, 


IXSECTS  INJURIOUS  TO  SMALL  GRAINS  145 

the  tip  of  the  abdomen  being  reddish  and  part  of  the  legs  whitish." 
This  species  has  been  taken  on  wheat  in  Illinois,  Nebraska,  Dela- 
,vare,  Maryland,  Ohio,  Indiana,  and  Pennsylvania.  During  1886 
and  1SS7  it  did  considerable  damage  by  cutting  off  the  heads, — 
sometimes,  as  stated  by  a  Maryland  man,  cutting  fully  one-half  of 
them.  No  more  recent  damage  has  been  recorded,  and  owing  to 
the  slight  injury  usually  clone  no  remedies  have  received  a  prac- 
tical test.  Deep  fall  plowing  might  be  of  advantage  by  burying 
the  larva^  so  deeply  that  the  adults  would  be  unable  to  escape. 

The  Wheat-midge  * 

Hisfonj. — While  the  Hessian  fly  attacks  the  stalk  of  the 
wheat-plant,  another  species  of  the  same  genus,  known  as  the 
Wheat-midge,  or  "  Red  Weevil,"  often  does  very  serious  damage 
to  the  maturing  head.  It,  too,  is  a  foreigner,  having  first  been 
noticed  as  injurious  in  Suffolk,  England,  in  1795,  though  probable 
references  to  its  depredations  date  back  as  early  as  1741.  "In 
'  Ellis's  Modern  Husbandman  '  for  1745  the  attacks  of  the  vast 
numbers  of  black  flies  (the  ichneumon  parasites)  are  noticed 
in  the  following  quaint  terms :  '  After  this  we  have  a  melancholy 
sight,  foi',  as  soon  as  the  wheat  had  done  blooming,  vast  numbers 
of  lilack  flies  attacked  the  wheat-ears  and  blowed  a  little  yellow 
maggot  which  ate  up  some  of  the  kernels  in  other  parts  of  them, 
and  which  caused  multitudes  of  ears  to  miss  of  their  fulness,  acting 
in  some  measure  like  a  sort  of  locust,  till  rain  fell  and  washed  them 
off;  and  though  this  evil  has  happened  in  other  summers  to  the 
wheat  in  some  degree,  yet  if  the  good  providence  of  God  had  not 
hindered  it  they  might  have  ruined  all  the  crops  of  wheat  in  the 
nation.'  (Hind's  'Essay  on  Insects  and  Diseases  Injurious  to 
Wheat  Crops,'  page  76)".  It  seems  probable  that  it  was  first 
introduced  into  America  near  Quebec,  where  it  "  appears  to  have 
occurred  "  iji  1819,  and  was  first  observed  in  the  United  States 

*  Diplosis  tritici.  Family  Cecidomyidie.  See  Bulletin  No.  5,  VoL  I,  2d 
Sex.,  Oliio  Ag.  Exp.  Sta.,  F.  M.  Webster. 


146       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  northwestern  Vermont  in  1S20.  It  did  not  become  very 
destructive,  however,  until  1828,  from  which  time  until  1835 
is  kept  increasing  in  such  numbers  as  to  cause  the  abandonment 
of  the  wheat  crops  in  some  localities  throughout  northern  New 
England.  Serious  damage  was  reported  as  due  to  this  pest 
every  few  years  until  about  1860,  being  most  severe  in  1854,  in 
which  year  Dr.  Fitch  estimated  the  loss  in  New  York  alone  at 
$15,000,000,  and  in  1857,  and  1858.  Since  then  no  widespread 
injury  has  occurred,  though  local  outbreaks  are  frequent,  and 


Fig.  106. — Wheat-midge  {Diplosh  tritici):  a,  female  fly;    fe,  male  fly;  c,  larva 
from  below.     (After  Marlatt,  U.  S.  Dept.  Agr.) 


it  has  spread  south  to  the  Gulf  States  and  westward  to  Iowa, 
Minnesota,  and  Arkansas. 

Life  History. — The  adult  flies  are  small,  two-winged  insects, 
about  an  eighth  of  an  inch  long,  of  a  yellow  or  orange  color. 
They  appear  about  the  middle  of  June  and  lay  the  eggs  "  in  a 
small  cavity  at  the  summit  of,  and  formed  by  a  groove  in,  the 
outmost  chaff  covering  the  incipient  kernel."  They  hatch  in 
about  a  week,  according  to  Dr.  Fitch,  and  the  maggots  burrow 
into  the  forming  kernels.  The  maggots  are  of  a  reddish  color, 
and  when  an  ear  is  badly  infested  give  it  a  reddish  tinge,  on 
account  of  which  the  insect  is  often  called   the  "  red  weevil." 


INSECTS  INJURIOUS  TO  SMALL  GRAINS  147 

When  full  grown  the  larvie  enter  the  ground  and  usually 
form  cocoons,  in  which  they  pass  the  winter  in  the  pupal  stage? 
though  they  often  hibernate  without  such  protection.  Though 
doubtless  there  is  usually  but  one  brood  in  a  season,  observations 
b}'  Professor  F.  M.  Webster  and  others  seem  to  point  to  the  fact 
that  there  sometimes  are  two  broods,  as  adults  have  been  ol)servcd 
from  August  into  November. 

Besides  wheat,  the  wheat-midge  also  sometimes  injures 
rye,  barley,  and  oats. 

Remedies. — Plowing  infested  fields  in  the  fall  so  deeply  that 
the  midges  will  be  unable  to  reach  the  surface  upon  developing 
in  the  spring  is  by  far  the  best  means  of  controlling  this  pest, 
while  Inirning  the  stubble  previous  to  plowing,  and  a  rotation 
of  the  crop,  will  also  be  of  considerable  aid. 

The  English  Grain-louse  * 

The  most  common  plant-louse  affecting  wheat  and  other  small 
grains  is  a  large  green  species  which  is  always  to  be  found  on 
wheat  plants,  but  which  occasionally  increases  very  rapidly,  and 
clustering  on  the  ripening  heads  sucks  the  juices  so  as  to  seriously 
injure  the  quality  and  weight  of  the  wheat. 

In  the  North  the  first  individuals  are  found  on  3'oung  wheat 
in  April,  though  dui'ing  open  winters  they  may  be  found  on  the 
plants,  and  in  the  South  they  continue  to  reproduce'  during  most 
of  the  winter  in  open  seasons.  The  aphides  feed  upon  the  leaves 
until  the  grain  commences  to  head,  when  they  assemble  on  the 
heads  among  the  ripening  kernels.  The  females  give  birth  to 
live  young,  bearing  from  40  to  50  each,  which  become  full  grown 
in  ten  days  to  two  weeks,  and  then  reproduce,  as  is  the  usual 
method  of  reproduction  with  plant-lice  (see  page  442),  so  that  they 

*  Macrosiphum  granaria  Buckton.  Family  Aphididte.  A  nearly  related 
species,  Macrosiphum  cerealis  Ksdtenhiich,  has  very  similar  habits,  is  commonly 
associated  with  the  species,  and  has  not  been  distinguished  from  it  by  most 
WTiters.  It  may  be  recognized  by  lackins;  the  blackish  markings  on  the 
abdominal  segments.  See  Pergande,  Bulletin  44,  Bureau  of  Entomology, 
U.  S.  Dept.  Agr. 


148        INSECT  PESTS  OF  JFARM,  GARDEN  AND  ORCHARD 


multiply  with  great  rapidit}',  and  where  so  few  were  present  as 
to  be  hardly  noticeable,  in  a  few  weeks  they  will  be  swarming 
over  the  heads  in  myriads.  As  the  small  grains  ripen  they  migrate 
to  various  grasses  and  are  not  much  in  evidence  during  midsummer, 
but  later  migrate  to  volunteer  oats  and  wheat,  upon  which  they 
subsist  until  fall  wheat  is  available.  Owing  to  the  cool  weather 
of  fall  and  the  fact  that  ]:)ut  few  individuals  survive  the  attacks 
of  their  parasites  during  the  summer,  they  rarely  become  aljundant 
enough  to  do  any  damage  to  grains  in  the  fall.     So  far  as  known, 

they  hibernate  over 
winter  among  the  leaves 
of  the  growing  plants, 
enough  surviving  l)oth 
snow  and  cold  to  infest 
the  crop  the  next  spring. 
Whether  true  males  and 
females  produce  eggs  on 
the  grain  is  unknown,  for 
though  they  have  been 
reared  under  artificial 
conditions,  they  have 
never  l^een  observed  in 
the  field.  Professor  F.  L. 
Washburn  observed  at 
least  fourteen  generations 
up  to  November  8,  1907, 
in  southern  Minnesota. 
As  with  other  aphides,  both  winged  and  wingless  individuals 
occur  throughout  the  season.  The  wingless  individuals  are 
about  one-tenth  inch  long,  with  l)lack  antennae  as  long  or  longer 
than  the  hody,  are  of  a  yellowish-green  color,  often  slightly 
pruinose,  and  long  black  nectaries  extend  from  either  side  of  the 
abdomen.  The  winged  individuals  are  about  the  same  length, 
with  a  wing  expanse  of  about  three-eighths  inch,  with  antenna? 
a  third  longer  than  the  body,  and  are  of  the  same  general  colora- 
tion except  that  lobes  of  the  thorax  are  brown  or  l^lackish,  and 


Fig.  107. — The  German  grain  aphis  {Macro- 
siphum  cerealis  Kah):  a,  winged  migrant; 
b,  nymph  of  same;  c,  wingless  partheno- 
genetic  female;  d,  same  showing  exit  hole 
of  parasite — enlarged,  (.\fter  Riley,  U. 
S.   Dept.  Agr.) 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


149 


the  abdomen  is  marked  with    four  or  five    transverse   blackish 

spots  in  front  of  the  nectaries. 

Like  the  other  apliides  affecting  small  grains,  this  species  is 

held  in  check  by  parasitic  insects,  aided  by  predaceous  insects  and 

fungous  diseases.     Injury  by  the  aphides  is  usually  due  to  the 

parasites  having  been  killed  off,  thus 
giving  the.  aphides  opportunity  to 
multiply  unchecked.  Among  the  most 
abundant  parasites  are  species  of  the 
genus  Aphidius  (family  Braconidce), 


Fig.  108. — Grain  aphides 
clustered  on  wheat  head, 
greatly  enlarged.  (After 
Weed.) 


Fig.  109. — Wheat-louse  parasite  (Aphidius 
avenaphis  Fitch),  and  parasitized  louse 
from  which  it  has  issued.  (Copied  from 
J.  B.  Smith.) 


one  of  which  is  shown  in  Fig.  109,  greatly  enlarged.  Cold,  wet 
weather  in  spring  greatly  retards  the  development  of  these  para- 
sites, so  that  the  aphides  are  always  more  numerous  in  such 
seasons.  It  has  also  been  ol^served  that  an  outbreak  is  often 
preceded  by  several  dry  seasons,  which  may  be  due  to  the  fact  that 
such  dry  seasons  check  the  development  of  fungous  diseases  which 
kill  off  large  numbers  of  the  aphides  and  which  do  not  propagate 
in  hot  dry  weather.     Thus  weather  conditions  are  very  intimately 


150      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

associated  with  the  abundance  of  the  pest.  When  the  parasites 
become  abundant  they  will  often  completely  rid  a  field  of  the 
aphides  within  a  few  days.  All  of  the  common  ladybird-beetles 
(Coccinellidce),  Syrphus-fiy  larvae,  and  lace- winged  fly  larvae 
(Chrysopidce)  are  commonly  found  f(H^ding  upon  the  aphides. 
Control. — No  practical  remedy  for  this  species  is  known  nor 
are  means  of  control  easily  suggested.  The  suppression  of 
volunteer  wheat  and  oats  in  early  fall  will  prevent  the  multiplica- 
tion of  the  pest  before  fall-sown  wheat  is  available,  and  the  late 
sowing  of  wheat  in  the  fall  will  reduce  the  numbers  entering 
hibernation.  A  wise  rotation  and  the  thorough  preparation 
of  the  seed-bed  and  liberal  fertilization  will  be  of  value  in  avoid- 
ing injury  in  the  same  way  as  has  been  described  for  other  pests 
of  small  grains.  Fortunately  this  spscies  rarely  does  very  wide- 
spread injury  and  its  parasites  usually  soon  bring  it  under  control. 

The  Spring  Grain-aphis  or  Green  Bug  * 

Though  long  known  as  a  serious  pest  of  small  grains  in  Europe, 
this  aphis  has  done  widespread  injury  in  this  country  only  during 
the  past  ten  years.  Though  it  occurs  throughout  the  territory 
north  of  latitude  41°,  with  the  exception  of  the  North  Atlantic 
States,  as  far  west  as  longitude  105°,  the  worst  injury  has  been  done 
in  northern  Texas,  Oklahoma,  and  Kansas,  though  it  has  also  been 
injurious  in  the  Carolinas  and  Tennessee. 

The  habits  of  the  insect  during  the  winter  have  not  been  suffi- 
ciently studied  to  speak  authoritatively,  but  it  seems  probable 
that  it  normally  passes  the  winter  in  the  egg  stage,  the  small  shin- 
ing black  eggs,  one-fortieth  inch  long,  being  laid  on  the  leaves  in 
the  late  fall.  In  the  South,  however,  it  often  continues "  to 
reproduce  throughout  the  winter,  and  with  a  mild  winter  the 
numbers  so  multiply  that  unless  checked  by  parasites  serious 
injury  is  done  by  late  winter  or  early  spring.  Both  wingless  and 
winged  forms  occur  throughout  the  year.  The  wingless  female 
is  from  one-twenty-fifth  to  one-fourteenth  inch  long,  yellowish- 
green,  with  a  median  line  slightly  darker,  eyes  and  most  of  the 
*  Toxoptcra  graminum  Rond.     Family  Aphididoe. 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


151 


antenriiP  black,  of  the  shape  shown  in  Fig.  112.  The  winged 
female  is  slightly  larger,  with  a  wing  expanse  of  about  one- 
quarter  inch,  and  of  the  same  general  coloration,  except  that  the 
head  is  brownish-yellow  and  the  lobes  of  the  thorax  are  blackish. 
The  aphides  hatching  from  the  eggs  are  all  females,  which  give 
birth  to  live  young,  no  male  forms  occurring  during  the  summer. 
During  her  life  of  slightly  over  a  month  a  female  will  give  birth  to 
50  or  60  young,  which  commence  to  reproduce  in  the  same  manner 


Fig.  110. — The  spring  grain-aphi.s  or  "green  bug"  (Toxoptera  gramimum) : 
a,  winged  migrant;  b,  antenna  of  same,  a,  much  enlarged;  b,  highly 
magnified.     (From  Pergande,  U.  S.  Dept.  Agr.) 


when  about  seven  days  old,  so  the  numbers  of  the  pest  obviovish' 
increase  with  enormous  rapidity,  and  with  thousands  of  tiny  beaks 
pumping  out  the  sap  the  young  grain  plants  soon  succuml).  The 
rate  of  reproduction  and  growth  is,  of  course,  much  slower  in 
colder  weather,  the  above  being  the  average  for  the  growing  season. 
Thus  in  an  open  winter  the  aphides  will  continue  to  multiply,  and 
by  February,  in  northern  Texas,  small  spots  of  wheat  and  oats 
will  show  the  effect  of  their  work,  by  March  the  injury  may  become 
widespread  and  serious,  and  by  the  middle  of  "April  the  crops  may 
be  ruined.    As  the  aphides  become  excessively  abundant  and  the 


152     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

food  supply  disappears,  almost  all  develop  wings,  and  immense 
clouds  of  the  winged  females  are  carried  northward  by  the 
winds,  so  that  an  outbreak  in  early  spring  in  the  South  leads  to  an 
infestation  farther  north,  and  excessive  multiplication  will  again 
carry  the  pest  still  northward,  progressing  in  that  direction  as  it 
increases  during  the  season,  rather  than  being  spread  at  one  time. 
Thus  in  1907  it  became  abundant  in  Oklahoma  in  April,  in  Kansas 


1 

*■■  (r 

*1 

i 

1 

Fig.  hi. — Green  bugs  on  oat-scedling — enlarged. 

in  May,  and  by  July  it  was  found  in  Minnesota,  where  it  rarely 
occurs  and  does  no  damage.  With  the  maturing  of  wheat  and  oats 
the  aphides  migrate  to  various  grasses,  being  particularly  fond  of 
Kentucky  blue-grass,  and  may  subsist  on  corn,  on  which  they 
may  feed  until  oats  and  wheat  are  available  in  the  fall.  Oats  are  the 
favorite  food,  and  outbreaks  of  the  pest  have  always  been  worst 
where  volunteer  oats  are  generally  grown,  the  aphides  increasing 
on  them  in  the  early  fall  and  winter  and  later  spreading  to  wheat. 
By  October  15th  in  Minnesota  and  by  early  November  in  Kansas 
the  true  winged  males  and  wingless  egg-laying  females  have  been 


INSECTS   INJURIOUS  TO  SMALL  GRAINS 


153 


observed,  but  strangely  enough  they  have  only  been  secured  in 
small  numbers  by  being  reared  in  the  laboratory,  and  have  not 
been  observed  in  the  field,  so  that  although  these  females  laid  eggs 
freely  on  the  leaves  of  grain,  we  do  not  know  whether  they  are 
essential  or  not  to  the  life  history  of  the  insect  in  the  field,  for 
while  the  eggs  are  being  produced  other  females  continue  to  give 
birth  to  live  young  until  the  cold  of  winter,   and   they  have  been 


Fig.  112. — Toxoptcra  gramiaum:   o,  newly  born,  and  b,  adult  wingless  green 
bug,  greatly  enlarged.     (After  S.  J.  Hunter.) 

observed    to  reproduce  with    a  daily  mean    temperature  barely 
above  freezing. 

Natural  Control. — The  natural  control  of  this  most  destructive 
pest  involves  a  most  interesting  relationship  between  temperature 
and  the  development  of  the  parasites  which  check  its  development. 
"  The  '  green  bug  '  in  normal  years — that  is,  when  its  breeding 
begins  in  spring — is  effectively  held  in  check  by  its  natural  ene- 
mies, and  notably  by  a  minute,  black  wasp-like  insect,  Lysiphlebus 
testaceipes Cress.  (Fig.  113),  that  deposits  eggs  singly  in  the  'green 


154      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

bugs,'  the  grubs  hatching  from  the  eggs  feeding  internally  on  the 
bug  and  destroying  it  (Figs.  115,  116).  Other  natural  enemies  are 
the  larvae  of  certain  predaceous  flies,  and  the  larvae  and  adults  of 
lady-beetles.  The  little  wasp-like  parasite  first  mentioned,  how- 
ever, is  the  one  that  keeps  the  '  green  bug  '  in  control  in  normal 
years,  and  in  years  when  the  latter  is  most  abundant  finally  over- 
comes it,  as  was  the  case  in  1907  in  Kansas,  North  CaroHna,  and 
other  States  in  the  more  northern  part  of  the  range  of  the  pest." 


Fig.  113. — Lysiphlebus  testaceipes  Cress.,  adult  female  and  antenna  of  male — 
greatly  enlarged.     (After  Webster,  U.  S.  Dept.  Agr.) 

"Unfortunately  this  parasitic  wasp — as  with  the  other  bene- 
ficial insects — is  active  only  while  the  temperature  is  above  56°  F., 
or  at  least  10°  above  that  at  which  the  '  green  bug  '  breeds  freely; 
and  herein  is  the  whole  secret  of  the  irregular  disastrous  outbreaks 
of  the  '  green  bug '  in  grain  fields.  As  accounting  for  the  out- 
break in  the  year  1907,  the  '  green  bug  '  had  had  a  whole  winter 
and  the  following  late  spring  in  which  to  breed  and  multiply  un- 
molested, and  it  accomplished  its  principal  damage,  as  in  Texas 
and  southern  Oklahoma,  before  the  weather  was  warm  enough 
for  the  parasite  to  increase  sufficiently  to  overcome  it." 


INSECTS  INJURIOUS  TO  SMALL  GRAINS 


155 


"  As  further  illustrative  of  th(^  important  bearing  of  weather 
conditions,  it  is  found  that  in  the  case  of  the  three  important  out- 
breaks of  this  insect,  namel}-,  for  the  years  1890,  1901,  and  1907, 
the  temperature  for  the  first  five  months  of  each  of  these  years, 
including  the  latter  part  of  the  winter  and  spring,  was  above  the 
normal  for  the  winter  months  and  below 
the  normal  for  the  spring  months;  in 
other  words,  warm  winters  and  cold,  late 
springs." 

''  The  little  parasitic  wasp  which  is  so 
useful  in  the  control  of  this  pest  is  native 
to  this  country,  widely  distril)uted,  and 
every  year  does  its  work  with  the  '  green 
bug '  and  with  other  aphides.  It  is 
always  present  in  grain  fields,  as  shown  by 
its  appearance  every  year,  to  war  on  these 
pests  whenever  the   weather  conditions 


Fig.  115. — Dead  "green 
bugs,"  showing  hole 
from  whicli  the  matu- 
red parasite  of  Lysiph- 
lebus  emerges.  The 
top  figure  shows  the 
hd  still  attached,  but 
pushed  back;  the  bot- 
tom figure  shows  the 
parasite  emerging. 
Enlarged.  (After 
Webster,  U.  S.  Dept. 
Agr.) 


Fig.  114. — Lifsiphlebiis  parasite  in  act  of  depositing 
eggs  in  the  body  of  a  grain-aphis — much  enlarged. 
(.\fter  Webster,  U.  S.  Dept.  Agr.) 


make  its  breeding  and  multiplication  possible,  and  its  rate  of  breed- 
ing is  so  rapid  (there  being  a  generation  al^out  every  ten  days)  that 
with  a  week  or  two  of  favorable  weather  it  gains  control  over  its 
host  insects  and  destroys  them."  *  Extensive  experiments  were 
conducted  in  Kansas  in  1907  in  importing  these  parasites  from 

*  From  F.  M.  Webster,  Circular  93,  Bureau  of  Entomology,  U.  S.  Dept. 
Agi-.  See  also  Bulletin  of  the  University  of  Kansas,  Vol.  IX,  No.  2,  by 
S.  J.  Hunter,  The  Green  Bug  and  Its  Natural  Enemies. 


156        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

farther  south  before  they  had  iDccome  abundant  in  Kansas  fields 
so  as  to  hasten  their  control  of  the  aphides,  but  further  experi- 
ments will  be  necessary  before  it  can  ])e  determined  whether  such 
a  method  of  colonizing  the  parasites  is  practically  effective  or  not. 
Control. — Most  important  of  all  methods  of  control  is  the  aban- 
donment of  the  growing  of  volunteer  oats  and  the  destruction  of 
all  volunteer  oats  and  wheat  in  the  early  fall.     Universal  experi- 


FiG.     116. — Parasitized 


:;reen    l)Hiis  — onlargoi 
S.  J.  Hunter.) 


(^From    ptiotograph,     alter 


ence  throughout  the  injured  area  shows  that  relatively  little  injury 
occurs  where  volunteer  oats  are  not  grown. 

Where  small  spots  of  grain  have  been  injured  by  the  pest  in  late 
winter,  which  is  the  way  an  outbreak  usually  begins  in  southern 
localities,  the  aphides  on  these  small  spots  may  be  killed  by  spray- 
ing with  10  per  cent  kerosene  emulsion,  or  whale-oil  soap,  5  pounds 
to  a  barrel  of  water,  by  covering  the  spots  with  straw  and  burning, 
or  by  plowing  under  the  infested  spots.  Were  this  generally  done 
before  the  aphides  commence  to  multiply  rapidly,  it  is  entirely 
possible  that  widespread  injury  might  be  averted. 


CHAPTER  IX. 
INSECTS  INJURIOUS  TO  CORN 


The  Western  Corn  Root-worm  * 

Throughout  the  corn  States  of  the  northern  Mississippi  Val- 
ley, wherever  corn  is  grown  upon  the  same  land  it  is  subject  to 
serious  injury  by  the  Western  Corn  Root-worm,  so  called  because 
it  first  became  injuri- 
ous   in    Missouri    and 
Kansas  and  gradually 
spread     eastward    to 
Ohio,  though  not    in- 
jurious  south   of   the 
Ohio  River. 

Though  the  life 
history  of  the  insect 
has  not  been  entirely 
determined,  the  fol- 
lowing sum  m  arizes 
it  as  observed  by 
Professors    S.   A, 

Forbes  and  F.  M.  Webster  in  Illinois  and  Indiana.  The  eggs 
are  laid  in  the  earl}'  fall,  within  a  few  inches  of  the  base  of  the  stalk, 
and  just  beneath  the  surface  of  the  soil.  The  egg  is  a  dirty  white 
color,  oval  in  shape,  and  about  one-fiftieth  inch  long.  The  winter  is 
passed  in  the  egg  stage,  differing  from  most  nearly  related  beetles  in 
this,  and  the  eggs  hatch  in  the  spring  or  early  summer.  At  first 
the  larvae  eat  the  small  roots  entire,  but  later  burrow  under  the 
outer  layers  of  the  larger  roots,  causing  the  stalks  on  rich  loam  to 

*  Diabrotica  longicornis  Say.     Family  Chrysomelidoe. 

157 


Fig.  117. — The  western  corn  root -worm:  a, 
beetle;  b,  larva;  c,  enlarged  leg  of  same;  d, 
pupa — all  enlarged.  (After  Chittenden,  U.  S. 
D.  Agr.) 


158         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

be  easily  blown  over,  or  dwarfing  the  plant  on  poorer  land  so  that 
it  produces  but  small  ears.  The  full-grown  larva  is  nearly  white 
with  a  brown  head,  a  little  less  than  one-tenth  inch  long  by  about 
one-tenth  inch  in  diameter.  Three  pairs  of  short  legs  are  found 
on  the  thorax,  but  otherwise  the  body  appears  perfectly  smooth 
to  the  eye,  though  finely  wrinkled.  Before  pupation  the  color 
becomes  slightly  darker  and  the  body  shortens.  Leaving  the 
roots,  the  larvae  then  form  small  oval  cells  in  the  soil  and  in  them 
transform  to  pupae,  from  which  the  adult  beetles  emerge  in  a 
short  time.  The  beetles  appear  from  the  middle  of  July  on 
through  August,  about  two  mor  ths  being  required  for  development 
after  hatching  from  the  egg.  The  beetles  are  of  a  greenish  or 
greenish-yellow  color,  about  one-quarter  inch  long,  and  resemble 
the  common  striped  cucumber-beetle  (page  379)  in  form.  They 
are  to  be  found  in  the  corn-fields  feeding  upon  pollen  and  silk 
until  the  latter  becomes  dry,  and  lay  their  eggs  during  August 
and  September.  The  beetles  are  often  found  feeding  upon  various 
weeds,  clover,  beans,  cucumber  and  squash  vines,  and  the  blossoms 
of  thistle,  sunflower  and  golden  rod. 

Control. — As  the  larva*  feed  only  on  corn,  if  the  corn-field  be 
planted  to  some  other  crop,  starvation  results,  and  a  simple  rota- 
tion in  which  corn  is  not  allowed  on  the  same  land  for  over  two 
years  in  succession  usually  prevents  injury,  though  a  field  in  which 
injury  has  occurred  should  be  planted  to  some  other  crop  at  once. 
It  is  imprudent  to  plant  corn  on  fields  in  which  the  beetle  has  been 
observed  feeding  in  large  numbers  on  clover  and  weeds  during  the 
late  fall  of  the  previous  year.  The  liljeral  use  of  manure  and  fer- 
tilizers, and  thorough  cultivation  will,  of  course,  be  of  service  in 
enabling  the  plants  to  withstand  attack. 

The  Southern  Corn  Root-worm  * 

Closely  related  to  the  last  species,  but  with  somewhat  different 
habits,  the  Southern  Corn  Root- worm  is  frequently  injurious  to 
corn  from  Maryland  and  southern  Ohio  southward. 

*  Dinhrotica  Vl-puncUita  Oliv.     Family  Chrymmelidoe. 


INSECTS  INJURIOUS  TO  CORN 


159 


The  adult  beetle  is  of  a  bright  green  marked  with  twelve  black 
spots,  which  have  given  it  the  name  of  12-Spotted  Cucumber- 
beetle  to  distinguish  it  from  the  Striped  Cucumljer-beetle  (page  379) , 
with  which  it  is  often  associated  feeding  on  cucurbs.  It  is  some- 
what larger  and  more  robust,  than  D.  longicornis,  and  is  almost 
omnivorous  in  its  food  habits,  feeding  upon  the  foliage  and  flowers 
of  a  long  list   of  forage  and  garden  crops,  to  which  it  often  does 


Fig.  lis. — The  southern  corn  root-worm:  a,  egg;  h,  larva;  c,  work  of  larva 
at  base  of  cornstalk;  d,  pupa;  e,  beetle — all  much  enlarged  except  c. 
(After  Riley.) 

considerable  damage.  Beans  are  frequently  injuretl  in  much  the 
same  way  as  corn  and  the  roots  of  melons  and  other  cuciirbs  are 
often  so  riddled  Ijy  the  larvte  as  to  kill  the  plants. 

Injury  to  corn  is  done  by  the  larvae  in  the  spring, when  they  feed 
upon  the  roots  while  the  corn  is  but  a  few  inches  high,  bore  into  the 
crown,  and  boring  into  the  base  of  the  stalk  through  the  young 
leaves  eat  out  the  "  bud."  The  latter  injuiy  often  seems  to  be 
more  serious  to  corn  than  the  injury  to  the  roots,  and  has  given 
the  insect  the  common  local  name  of  "  bud  worm,"  which  is 
unfortunatel}'  applied  to  several  other  insects  which  do   similar 


160      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

injury.  Larvae  have  been  found  attacking  wheat,  rye,  millet  and 
Johnson  grass  in  a  similar  way,  the  beetles  seeming  to  be  attracted 
to  fields  containing  Johnson  grass  before  the  corn  appears,  thus 
injuring  such  grassy  fields  more  severely.  Injury  to  corn  seems  to 
be  worse  on  low,  damp  spots. 

Life  History. — The  beetles  hil)ernate  over  winter  and  are 
among  the  first  insects  to  appear  in  early  spring,  appearing  by  the 
middle  of  March  in  the  Southern  States.  Eggs  are  laid  during  April 
in  the  Gulf  States  and  from  late  April  to  early  June  in  Kentucky 
and  the  District  of  Columbia.  The  egg  is  dull  yellow^,  oval,  and 
about  one-fortieth  inch  long.  The  eggs  are  laid  singly  just  beneath 
the  surface  of  the  soil  and  hatch  in  from  seven  to  ten  days,  those 
laid  early  in  the  season  recjuiring  considera])ly  longer.  The 
larva)  become  full  grown  and  pupate  about  a  month  later,  the 
adult  beetles  of  the  first  generation  appearing  during  May  and 
early  June  in  the  Gulf  States  and  in  late  June  and  early  July  in  the 
District  of  Columliia  and  Kenturky.  Thus  the  complete  life  cycle 
requires  from  six  to  nine  weeks  in  the  spring.  Eggs  are  laid  l)y  the 
first  generation  of  Ijeetles,  the  larva'  l)eing  found  on  the  roots  of 
corn  from  midsummer  until  fall,  when  the  second  generation  of 
beetles  is  found  in  October  and  November  in  Kentucky.  In  the 
Gulf  States  there  are  undoubtedly  three  complete  generations, 
though  they  have  not  l^een  carefully  followed.*  The  beetles 
assemble  on  clover  and  alfalfa  in  the  late  fall,  upon  which  they  feed 
until  winter  sets  in,  and  often  come  out  and  feed  during  warm 
spells  in  January  and  Febi'uarv  in  the  Soutliern  States. 

Control. — Although  rotation  of  crops  will  not  be  as  effective  in 
the  control  of  this  species  as  in  the  case  of  D.  Jongicornis,  it  will 
undoubtedh'  l^e  found  of  value  to  avoid  planting  corn  in  succession 
where  injury  is  probaljle.  By  planting  late  after  the  beetles  have 
laid  their  eggs,  injury  has  been  avoided  in  Georgia.  Liberal  seed- 
ing, using  ten  grains  of  seed  per  hill,  will  give  a  sufficient  stand 
free  from  attack,  so  that  by  thinning  a  good  stand  may  be  secured. 

*  In  the  Northorn  States,  where  this  species  is  not  a  pest  of  com,  but  is 
common  on  cvicurl)s  antl  garden  plants,  there  is  probably  but  a  single  genera- 
tion with  a  life  history  very  similar  to  that  of  the  striped  cucumber-beetle, 
see  page  379. 


INSECTS  INJURIOUS  TO  CORN  '  161 

Fields  which  are  well  infested  with  Johnson  grass,  or  other  thick- 
stemmed  grasses,  should  l)e  avoided,  for  as  already  indicated  the 
beetles  will  be  attracted  to  them  ])(>fore  the  corn  is  up.  Both 
on  account  of  the  feeding  hal^its  of  the  larvae  and  the  migratory 
habits  of  the  beetles  no  insecticide  treatment  commends  itself  as 
practicable. 

The  Corn-root  Webworm  * 

Injury. — When  young  corn-plants  are  seen"  to  stop  growing, 
become  deformed,  and  to  die  off  in  such  numbers  as  to  frequently 
necessitate  replanting,  upon  examination  of  the  roots  the  injur}' 
w'll  sometimes  be  found  to  be  due  to  the  work  of  a  small  caterpillar. 
Two  or  three,  very  often  five  or  six,  and  sometimes  as  many  as 
eight  or  nine  will  bo  found  at  the  base  of  a  plant  al^out  an  inch 
below  the  surface  of  the  soil,  and  not  over  -1  to  6  inches  from 
the  stalk,  usually  being  in  close  proximity  to  it.  If  each  larva  is 
covered  with  a  fine,  loose  wel),  to  which  cling  particles  of  earth 
forming  a  sort  of  case,  it  is  probal)ly  a  corn-root  webworm. 

Where  the  webworms  are  present  in  any  number  tho}^  will 
often  necessitate  a  second,  third,  or  sometimes  a  fourth 
planting,  making  the  corn  very  late  and  involving  considerable 
expense.  The  worms  bore  into  the  young  stalks  just  above  the 
ground,  frequently  cutting  them  off  entirely.  Later  on  the 
larger  stalks  are  gouged  out  at  or  slightly  above  the  surface  of 
the  ground,  and  the  larva)  burrow  into  the  folded  leaves,  which 
when  they  unfold  have  several  transverse  rows  of  three  to  five 
holes.  On  account  of  this  habit  these  insects  are  sometimes 
known  as  "  budworms."  Strong  plants  will  often  make  a  new 
start  and  survive  the  injury,  Init  remain  much  behind  those  not 
attacked,  while  most  of  the  weaker  plants  will  decay  and  rot  off. 

The   Moth. — As   one  walks  through   pasture   or  grass  land, 

many  little  white   and   yellowish   moths   are   seen  flying   about 

on  all  sides,  but  quickly  disappear  as  they  alight  on  the  grass. 

"If  a  single  individual  be  watched  more  closely,  it  will  be  noticed 

that  in  alighting  upon  a  blade  of  grass  it  quickly  rolls  its  wings 

*  Crambus  caliginosellus  Clem.     Family  Crambidce. 


162         JXSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


very  tightly  around  its  body,  and  hugs  up  close  to  the  grass 
so  that  it  is  hardly  distinguishable  from  it.  Projecting  from  the 
head  in  front  is  what  appears  to  be  a  long  beak  or  snout,  on 

account  of  which 
these  moths  are 
often  known  as 
"snout-moths/'  but 
which  really  con- 
sists of  the  palpi 
or  feelers.  The 
"  grass-moths,"  as 
they  are  sometimes 
called,  belong  to  the 
genus  Crambus  and 
include  several 
c  o  m  m  o  n  species, 
which  are  marked 
with  silver  stripes 
and  bands,  as  well 
as  golden  lines  and 
markings,  so  that 
they  often  present 
a  very  handsome 
appearance. 

Life  History. — 
These  are  the  pa- 
rents of  the  web- 
worms  which  do  so 
much  injury  to  the 
young  corn-roots, 
the  principal  depre- 
dators upon  corn 
belonging  to  the 
their   eggs   in  grass 


Fig.     119.— The 
caliginonellus 


segment  of  larva;  e,  parasite. 


weD-wonn     {Cramhufi 
b,    pupa;    c,  moth;  </, 


(.\fter  Johnson.) 
They    lay 


species  Crambus  caliginosellus. 

land    in    May    or    early    June,    dropping    them    on   the    surface 

among    the    rubbish    or    vegetation,    or  attaching  them  to  the 


INSECTS   INJURIOUS  TO  C(3RN  163 

grass.  They  are  oval  in  form  and  of  a  yellowish  color,  each 
being  marked  with  regularly  placed  ridges.  About  two  hundred 
eggs  are  laid  by  each  female.  In  from  six  to  ten  days  the 
eggs  hatch.  The  young  larva?  soon  form  their  loose  silken  webs 
or  tubes  at  or  a  little  below  the  surface  of  the  soil,  burrowing 
among  the  roots,  and  feeding  upon  the  stalk  and  outer  leaves, 
or  killing  the  plant  by  attacking  the  crown.  The  larvse  vary 
considerably  in  color,  from  a  yellowish  white,  through  pink, 
to  a  reddish  or  brownish  shade,  and  are  studded  with  small 
tubercles,  each  bearing  a  tuft  of  bristly  hairs.  The  larvae  become 
full  grown  in  from  five  to  seven  weeks  and  are  then  from  one- 
half  to  three-fourths  of  an  inch  long.  During  the  latter  part  of 
July  they  form  cocoons,  sometimes  in  the  larval  tubes,  in  which 
they  pass  the  pupal  stage  and  from  which  the  moths  emerge 
some  twelve  to  fifteen  days  later.  Eggs  are  laid  for  another 
brood  in  grass  lands  during  August  and  September,  the  larvso 
hatching  in  September  and  October  and  becoming  partly  grown 
before  winter.  They  hibernate  in  their  webs  over  winter,  and  as 
soon  as  the  grass  commences  its  growth  in  the  spring  they  are 
to  be  found  feeding  upon  it,  becoming  full  grown  early  in  May. 
Preventive. — As  the  natural  food  of  these  insects  is  grass,  it 
is  not  surprising  that  corn  planted  on  sod  land  should  be  worst 
injured;  and  though  the  injury  clone  the  grass  may  not  have  been 
noticeable,  when  the  available  food  is  so  greatly  diminished  by 
substituting  for  grass  the  comparatively  few  hills  of  corn  the 
injury  becomes  much  more  serious  and  apparent.  Though  the 
planting  of  corn  on  sod  land  is  a  most  common  practice,  injury 
by  this  and  many  other  insect  pests  of  corn — most  of  whose 
native  food  is  grass — might  be  avoided  by  planting  any  other 
crop  than  a  grain,  such  as  potatoes.  Otherwise  plowing  late  in 
the  fall  and  harrowing  so  as  to  expose  the  larvsE  to  the  weather, 
or  plowing  so  deeply  that  they  will  be  l)uried  so  that  they  cannot 
regain  the  surface,  will  do  much  to  prevent  injury  the  next  season. 
Inasmuch  as  the  moth  will  not  lay  her  eggs  upon  plowed  land, 
if  the  land  be  plowed  early  she  will  be  driven  to  other  fields; 
but  the  exact  time  of  oviposition  varies  for  different  latitudes. 


164        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Generous  fertilization  will  aid  the  plants  in  overcoming 
injury  very  considerably.  Dr.  J.  B.  Smith  advises  "  the  applica- 
tion of  all  the  necessary  potash  in  the  form  of  kainit,  put  on  as 
a  top-dressing  after  the  field  is  prepared  for  planting,"  and  says: 
"Fall  plowing  and  kainit  as  a  top-dressing  in  spring  will,  I  feel 
convinced,  destroy  by  all  odds  the  greater  proportion  of  the  web- 
worms  that  infest  the  sod,  and  would  also  destroy  or  lessen  many 
other  pests  which  trouble  corn  during  the  early  part  of  its  life." 

The  Corn-root  Aphis  * 

Where  patches  of  corn  become  dwarfed,  the  leaves  becoming 
yellow  and  red,  with  a  general  lack  of  vigor,  the  grower  may  well 
be  suspicious  of  the  presence  of  the  Corn-root  aphis.  These 
little  aphides,  which  cluster  on  the  roots  of  corn,  are  a  bluish- 
green  color,  with  a  white  waxy  bloom,  and  of  the  form  shown  in 
Fig.  120.  Two  short,  slender  tubes  project  from  the  posterior 
part  of  the  abdomen  which  are  commonly  called  honey-tubes, 
because  they  were  formerly  supposed  to  give  out  the  honey-dew, 
which  is  so  relished  by  the  ants  which  tend  the  aphides  to  secure 
it.  The  winged  female  has  a  black  head  and  brownish-black 
thorax,  with  pale  green  abdomen  bearing  three  of  four  blackish 
marginal  spots  and  small  dark  specks  over  the  surface.  The 
antenna)  are  dark  and  the  legs  blackish. 

The  corn-root  aphis  occurs  throughout  the  principal  corn- 
growing  States,  but  has  been  most  destructive  where  corn  is 
most  extensively  grown  and  is  often  planted  year  after  year 
on  the  same  land.  Dr.  Forbes,  to  whom  we  are  indebted  for 
most  of  our  knowledge  of  this  pest,t  has  observed  fields  of  corn 
in  Illinois  planted  in  corn  for  the  second  season  totally  ruined 
by  the  root-aphis.  Broom-corn  and  sorghum  are  the  only  other 
cultivated  crops  which  have  been  injured,  but  the  list  of  food 
plants  includes  smartweed,  purslane,  ragweed,  foxtail,  and  crab- 

*  Aphis  maidi-radicis  Forbes.     Family  Aphididce. 

t  S.  A.  Forbes,  17th,  18th,  and  25th  Reports  of  the  State  Entomologist 
of  Illinois;  Bulletin  60,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  p.  29; 
Bulletins  104  and  130,  Illinois  Agr.  Exp.  Sta.  See  also  J.  J.  Davis,  Bulletin 
12,  Part  VIII,  Technical  Series,  Bureau  of  Entomology,  U.  S.  Dept.  Agr., 
and  y  M.  Webster,  Circular  86,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  CORN 


165 


grasses,  and  many  other  weeds  and  grasses  which  spring  up  in 
the  corn-field.  In  South  Carolina  Professor  A.  F.  Conradi  has 
found  it  injuring  cotton. 

If  the  nests  of  the  small  brown  ant  *  so  common  in  corn-fields 
infested  with  the  root-aphis,  l^e  broken  open  during  the  winter, 
many  of  the  little  black  aphis  eggs,  which  have  been  carefully 
stored  by  the  ants,  will  be  found.    They  are  a  glossy  black  color, 


Fig.  120. — The  com  root-aphis  (Aphis  maidi-radicis  Forbes) :  at  left,  ovip- 
arous female;  a,  hind  tibia,  showing  sensoria;  at  right,  male;  a,  antenna 
— much  enlarged.     (After  Forbes.) 

oval   in   shape,    and   will  sometimes  be  found  in  small  piles  in 

the  chambers  of  the  ants'  nests.     On  warm  days  the  ants  bring 

them  up  to  the  warmer  surface  soil  and  in  cold  weather  carry 

them  far  down  into  the  unfrozen  earth.     With  the  appearance 

of  young  smartweed  and  foxtail-grass  in  April  and  May  the  eggs 

commence  to  hatch.       The  ants  at  once  lay  bare  the  roots  of 

these  plants  and  carry  their  young  wards  to  them,  where  large 

colonies  soon  Ijecomc  established.     If  the  field  is  not  planted  in 

*  Lasiiis  niger  Linn.  var.  americanus  Emery.     See  Forbes,  Bulletin  131, 
Illinois  Agr.  Exp.  Sta. 


166        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

corn,  the  lice  will  feed  later  upon  the  roots  of  pigeon-grass  or 
purslane.     In  early  May  the  second  generation  of  lice  commence 


4  5 

Fig.  121. — ^The  corn-root  aphis  (Aphis  maidi-radicis  Forbes):  1,  wingless 
vivaparous  female;  a,  apex  of  abdomen;  2,  antenna  of  same;  3,  pupa; 
4,  -vidnged  vivaparous  female;    5,  antenna  of  same.     (After  Forbes.) 

to  appear,  among  them  being  both  wingless  and  winged  forms.       , 
This  brood  and  all  of  these  during  the  summer  are  produced  by 
females  known  as  agamic  females,  which  give  birth  to  live  young 


INSECTS  INJURIOUS  TO  CORN 


1G7 


without  mating  with  a  male.  As  soon  as  corn  plants  arc  available 
the  ants  again  transfer  the  aphides  to  their  roots,  and  carry  any 
winged  aphides  which  may  have  spread  over  the  field  down  on 
to  the  roots  of  the  corn.  All  through  the  summer  the  ants 
attend  the  lice,  burrowing  around  the  roots  of  the  corn,  and 
carrying  them  from  plant  to  plant,  in  return  for  which  the 
aphides  give  off  the  sweet  honey-dew,  when  stroked  by  the  ants' 
antennae,  upon  which  the  ants  feed.  During  the  summer  the 
aphides  continue  to  reproduce  with  extreme  rapidity,  an  aphid 
maturing  and  giving  birth  to  young  about  eight  days  after  it  is  born, 


Fig.    122. — Grass    root-louse    (Schizoneura    panicola);     winged    vivaparou.s 
female,     a,  antenna.     (After  Forbes.) 


each  generation  taking  about  sixteen  days  and  there  being  about 
twelve  generations  during  the  season.  Both  winged  and  wingless 
agamic  females  occur  throughout  the  summer,  but  late  in  Sep- 
tember and  in  October  wingless  forms  which  develop  into  true 
males  and  females  are  produced.  These  mate  and  the  females 
l^y  eggs  during  October,  most  of  them  being  carried  by  the  ants 
to  their  nests,  where  the  eggs  are  laid. 

Control. — Owing  to  the  fact  that  the  aphides  do  not  migrate 
until  the  second  generation,  a  rotation  of  crops  will  be  of  great 
service  in  checking  their  injuries,  as  corn  planted  on  uninfested 
land  will  not  be  attacked  until  it  has  been  able  to  secure  a  good 
start,  and  if  well  fertilized  will  be  able  to  successfully  withstand 


168         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  123. — The  corn-field  ant  {Lasius  niger  americanus) :  1,  worker;  2,  larva; 
3,  winged  male;  4,  pupa;  5,  winged  female;  6,  female  with  wings  re- 
moved.    (After  Forbes.) 


INSECTS  INJURIOUS  TO  CORN  169 

whatever  injury  may  occur.  Rarely  is  corn  on  land  not  in  corn 
the  previous  year  seriously  injured,  and  where  infestation  has 
not  been  serious  throughout  a  community,  it  may  usually  be 
grown  two  years  in  succession  with  safety. 

The  proper  fertilization  of  plants  affected  with  root  insects 
is  always  of  great  importance,  enabling  the  plant  to  make  a  crop 
in  spite  of  them  if  the  attack  is  not  too  severe.  Professor  F.  M. 
Webster  observes  that  land  which  has  been  fertilized  with  barn- 
yard manure  is  much  less  injured  Isy  this  insect  than  that  where 
commercial  fertilizers  are  used. 

As  the  ants  not  only  spread  the  pest  during  spring  and  sunmior, 
but  house  the  eggs  in  their  nests  over  winter,  an}'  means  for 
destroying  their  nests  will  be  of  importance  in  controlling  the 
aphides.  Where  it  is  practicable,  deep  plowing  in  late  fall  and 
winter,  with  thorough  harrowing,  will  1)reak  up  the  nests,  and 
land  so  treated  has  shown  decidedly  less  injury  the  next  season. 
Similarly  plowing  deeply  and  harrowing  several  times  in  spring 
not  only  breaks  up  the  ants'  nests,  but  destroys  the  weeds  and 
grasses  upon  which  the  aphides  feed  before  corn  is  up,  and  also 
furnishes  the  best  possible  seed-bed  and  soil  conditions.  This 
should  be  particularly  thorough  in  low  spots  where  weeds  are 
thickest  and  where  the  aphides  appear  first.  Such  spring  cultiva- 
tion has  been  demonstrated  as  very  effective  in  the  control  of 
the  pest.  In  recent  years  Professor  S.  A.  Forbes  has  conducted 
experiments  in  Illinois  which  seem  to  show  that  dipping  the  seed 
in  a  repcllant  such  as  a  lemon  oil  will  render  it  oljnoxious  to  the 
ants,  and  thus  protect  the  hill.  This  has  not  proven  successful, 
however,  when  heavy  rains  followed  planting  and  washed  off 
the  repellant.  Lemon  oil  was  used  by  adding  1  gallon  of  wood 
alcohol  to  1  pint  of  oil  of  lemon,  of  which  3  fluid  ounces  (6  table- 
spoonfuls)  were  stirred  into  each  gallon  of  seed  used,  being  sure 
that  all  the  seeds  were  well  coated.  Such  a  treatment  cost  about 
ten  cents  per  acre  and  resulted  in  reducing  the  number  of 
aphides  89  per  cent  and  the  number  of  ants  79  per  cent,  so  that 
it  may  well  be  given  a  trial,  but  the  chief  reliance  should  be  placed 
upon  rotation  and  early  cultivation. 


170         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Corn  Leaf -aphis  * 

Although  the  corn  leaf-aphis  is  not  often  very  seriously 
injurious  to  corn,  in  Texas  and  other  Southern  States  it  frequently 
becomes  so  abundant  on  sorghum  and  corn,  and  in  winter  on 
barley,  as  to  do  considerable  injury.  This  species  is  also  of  interest 
in  that  it  appears  on  corn  foliage. in  midsummer  at  the  time  when 
the  numl:)ers  of  the  root-aphis  commence  to  decrease  on  the  roots, 


Fig.  124. — The  com  leaf-aphis  {Aphis  maidis  Fitch) :    winged  female — much 
enlarged.     (After  Webster,  U.  S.  Dept.  Agr.) 

and  it  was  for  many  years  thought  to  be  the  same  species.  Care- 
ful rearing  experiments  made  under  the  direction  of  Dr.  S.  A. 
Forbes  have  failed  to  show  any  connection  between  the  root- 
aphis  and  leaf-aphis,  the  aphides  from  the  roots  being  unable  to 
establish  themselves  on  the  leaves  and  those  on  the  leaves  never 
migrating  to  the  roots. f 

Dr.  Forbes  describes  the  species  in  his  twenty-third  report 
as  follows:  "  In  the  latter  part  of  the  summer  this  bluish-green 
plant-louse  may  occasionally  be  found  on  the  younger  leaves, 

*  Aphis  maidis  Fitch.  Family  Aphididoe.  See  Webster  and  Davis, 
I.e.,  p.  164. 

t  S.  A.  Forbes,  13th,  16th,  18th,  and  23d  Reports  of  the  State  Entomologist 
of  Illinois. 


INSECTS  INJURIOUS  TO  CORN 


171 


the  tassel,  and  the  upper  part  of  stalks  of  corn,  and  more  abun- 
dantly and  frequently  on  broom-corn  and  sorghum.  Multiply- 
ing in  place  by  the  birth  of  living  young,  which  do  not  wander 
from  their  place  of  origin,  these  leaf-lice  may  become  abundant 
enough  to  kill  the  leaves  and  to  some  extent  to  effect  the  health 
of  the  plant.  The  insect  is,  however,  rarely  seriously  injurious 
to  corn,  but  there  is  some  evidence,  .  .  .  that  it  may  prevent  the 
fertilization  of  the  kernel  by  sucking  the  sap  from  the  silk  and 
killing  it  before  it  has  performed  its  function.  Heavily  infested 
corn  leaves  turn  yellow  or  red,  and  may  shrivel  and  die,  partic- 
ularly if  the  weather  be  dry  at  the 
time.  Broom-corn  is  consideralily 
damaged  by  a  reddened  discoloration 
of  the  brush,  due  to  a  bacterial  affec- 
tion following  upon  the  plant-louse 
punctures. 

"  The  wingless  form  of  this  aphis 
is  about  2  mm.  (one-twelfth  inch) 
long  and  half  as  wide  at  the  widest 
part,  the  body  being  somewhat  ovate 
in  outline.  The  general  color  is  pale 
green,  with  the  cauda,  cornicles  and 
the  greater  part  of  the  rostrum, 
antennae  and  legs  black.  The  head 
is     marked    with     two     longitudinal 

dark  bands,  and  the  abdomen  with  a  row  of  black  spots 
on  each  side  and  a  black  patch  about  the  base  of  the  cornicles. 
The  lattei  are  swollen  in  the  middle,  making  the  outlines  convex. 
.  .  .  The  winged  form  is  somewhat  different  in  color,  the  head 
being  black  and  the  thorax  chiefly  black  above.  The  abdomen 
is  pale  green,  bluish  at  the  sides,  with  two  transverse  black  bands 
preceding  the  cauda,  and  the  segments  behind  it  edged  with  dark." 
These  differences  between  this  and  the  root  aphis  are  shown  in 
the  accompanying  figures.  "Aphis  maidis  has  been  reported 
at  various  times  as  a  corn  insect  from  New  York  to  Texas, 
Minnesota   and   California.     The   species   makes   its   appearance 


Fig.  125. — The  wingless 
female  of  the  corn  leaf- 
aphis  —  much  enlarged. 
(After  Webster,  U.S.  Dept. 
Agr.) 


172      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  midsummer,  our  earliest  date  (Illinois)  being  July  9,  when 
specimens  were  found  on  young  leaves  of  corn.  We  have  no 
record  whatever  to  show  whence  it  comes  or  where  it  lives  pre- 
ceding this  time.  Having  once  commenced  to  breed  on  the  food 
plants  mentioned,  it  continues  there  until  freezing  weather  over- 
takes it,  when,  with  the  death  of  its  food  plants,  it  gradually 
disappears,  leaving  neither  eggs  nor  hibernating  adults  on  or 
about  these  plants,  and  passing  the  winter  we  do  not  know  how 
or  where."  Its  occurrence  on  barley  in  Texas  in  January  may 
throw  some  light  upon  its  wintering  habits  in  the  South.  ''  The 
latest  to  develop  in  the  field  largely  acquire  wings,  and  as  the  sap 
supply  in  the  plant  diminishes  they  fly  away.  Wingless  females, 
on  the  other  hand,  perish  on  the  spot.  Indications  are  thus 
very  strong  that  this  is  a  migrating  species  whose  second  food 
plant  is  thus  far  unknown." 

No  experiments  in  the  practical  treatment  of  this  pest  seem 
to  have  been  recorded. 

The  Larger  Corn  Stalk-borer  * 

Throughout  the  South  from  Maryland  to  Louisiana  and  west- 
ward to  Kansas  more  or  less  serious  injury  is  done  by  large  white, 
brown-spotted  caterpillars  which  bore  into  the  stalks.  In  spring 
the  young  caterpillars  bore  into  the  heart  of  the  young  plant  and 
like  other  insects  with  similar  habits  (seepage  161)  are  known  as 
"  budworms."  Later  the  hoUowing  out  of  the  stalk  so  weakens 
the  plant  that  it  is  readily  broken  over  by  the  wind.  Consequently 
a  loss  of  from  25  to  50  per  cent  of  the  crop  not  infrequently  results 
where  the  pest  is  abundant. 

Life  History. — When  the  caterpillars  become  full  grown  in  the 
fall  they  burrow  down  into  the  tap-root  and  there  pass  the  winter 
in  a  small  cavity  at  or  near  the  surface  of  the  ground.  About  the 
time  the  land  is  being  prepared  for  corn,  from  March  15  to  April  30, 
depending  on  the  locality,  the  larva  changes  into  a  reddish-brown 
pupa,  from  which  the  moth  emerges  in  ten  days  or  more.     The 

*  Diatraea  zeacolella  Dyar.  Family  Crambidce.  See  Circular  139,  Bureau 
of  Entomology,  U.  S.  Dept.  of  Agriculture. 


INSECTS  TXJURIOUS  TO  CORN 


173 


moth  is  a  brownish-yellow  color  with  wings  expanding  1|  inches, 
the  liind-wings  being  darker  and  bearing  faint  markings  (Fig.  128). 
The  eggs  are  laid  at  dusk  upon,  the  under  surface  of  the  leaves  of 
theyoung corn,  and  hatch 
in  from  seven  to  ten  days. 
The  eggs  are  flat,  scale- 
like, and  placed  in  rows 
of  from  two  to  twenty- 
five,  slightly  overlapping 
each  other.  They  arc 
Vioo  inch  long,  by  two 
thirds  as  wide,  at  first  a 
creamy-white,  but  grad- 
ually becoming  a  reddish 
brown.  The  young  larva 
bores  into  the  stalk,  often 
destroying  the  ''  bud," 
and  then  at  or  near  the 
ground,  where  it  burrows 
upward  in  the  pith, 
seldom  damaging  the 
stalk  above  the  third 
joint.  As  the  Ijorers 
grow  they  become  quite 
active  and  frequently 
leave  and  re-enter  the 
stalk,  thus  making  sev- 
eral holes.  The  caterpil- 
lars become  full  grown 
in  twenty  to  thirty 
days,  and  are  about  one  inch  long,  dirty-white,  thickly  covered 
with  dark  spots,  each  of  which  bears  a  short,  dark  bristle. 
The  mature  caterpillar  bores  outward  to  the  surface  of  the  stalk, 
making  a  hole  for  the  escape  of  the  adult  moth,  which  it  covers 
with  silk,  and  then  transforms  to  a  pupa  in  its  burrow.  This 
occurs  during  July,  and  the  moths  of  the  second  generation  emerge 


Fig.  126. — Work  of  the  larger  com  stalk-borer: 
a,  general  appearance  of  stalk  infested  by 
the  early  generation  of  borers;  b,  same 
cut  open  to  show  pupa  and  larval  burrow. 
(After  Howard,  U.  S.  Dept.  Agr.) 


174      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  seven  to  ten  days.     The  second  brood  of  larvae  feed  on  the  old 


Fig.  127. — a,  h,  c,  varieties  of  the  larva  of  the  larger  corn  stalk-borer;  d, 
third  thoracic  segment;  e,  eighth  abdominal  segment;  /,  abdominal 
segment  from  side;  g,  same  from  above — enlarged.  (After  Howard, 
U.  S.  Dept.  Agr.) 

stalks,  tunneling-  them  between  the  second  joint  and  the  ground, 

and  l)econi(>  full  grown  about 
harvest  time  when  they  gt) 
into  winter  quarters  in  the 
root  as  above  described. 

Control. — It  has  been 
observed  that  late  planted 
corn  is  much  less  injured 
than  that  planted  early, 
but  as  it  is  more  seriously 
injured  by  some  other  pests, 
<  late  planting  may  not  be 
advisable. 

Where  corn  has  been 
seriously  injured,  the-  old 
stalks  or  butts  should  be 
dragged   off  the    field   and 


Fig.  128. — The  larger  corn  stalk-borer. 
a,  female;  6,  wings  of  male;  r,  pupa 
— all  somewhat  enlarged.  (.\fter 
Howard,  U.  8.  Dept.  Agr.) 


burned  late  in  the  fall,  thus  destroying  the  over-wintering  borers. 


INSECTS  INJURIOUS  TO  CORN  175 

When  corn  is  stripped  for  fodder,  the  stalks  left  standing  and  the 
land  sown  in  small  grain,  the  most  favorable  conditions  arc 
allowed  the  borers  for  safely  passing  the  winter  and  developing 
into  moths  which  will  fly  to  new  fields  in  the  spring. 

A  simple  rotation  of  crops  will  also  lessen  injury  considerably, 
as  Dr.  L.  0.  Howard  has  observ^ed  that  where  fields  which  had 
been  in  corn  the  previous  year  were  damaged  25  per  cent,  those 
planted  on  sod  land  were  damaged  but  10  per  cent,  though  reason- 
ably close  to  land  which  had  been  in  corn. 

Bill-bugs  * 

Throughout  the  South  and  often  in  the  more  Northern  States, 
.Canada,  and  the  West  the  bill-bugs  sometimes  become  serious 
enemies  of  young  corn-plants.  They  are  called  "  bill-bugs  "  on 
account  of  the  prolongation  of  the  head,  termed  a  bill  or  snout, 
peculiar  to  all  the  weevils  or  "  snout-beetles,"  by  means  of  which 
they  are  enabled  to  drill  holes  in  the  corn-stalks.  Several  species 
belonging  to  the  genus  Sphenophorus  are  commonly  injurious  to 
corn.  One  of  these,  S.  parvidus  Gyll.,  also  attacks  small  grains 
and  timothy,  and  is  therefore  known  as  the  Grain  Sphenophorus. 
Another  species,  S.  obscurus  Boisd.,  does  considerable  injur}-  to 
sugar-cane  in  Hawaii.  The  adult  beetles  are  from  one-fourth  to 
three-fourths  of  an  inch  long,  of  the  form  shown  in  the  illustration^ 
and  are  of  a  brown  or  black  color,  marked  with  darker  longitudinal 
ridges  on  the  wing-covers.  The  larva  is  a  thick  fleshy  white 
grub,  from  one-fourth  to  five-eighths  of  an  inch  long,  with  a 
brown  head  and  cervical  shield  on  the  first  segment,  and  footless. 

Life  History. — The  life  histories  of  the  different  species  are 
but  partially  known. 

S.  parvulus  hibernates  over  winter  as  a  beetle,  appearing  in 
March  and  April.  The  female  punctures  the  stalk  of  wheat  or 
timothy — oats  and  barley  are  also  sometimes  attacked — a  little 
above  the  roots,  and  deposits  her  egg  in  the  cavity.  This  is  done 
in  May  or  June  or  even  up  to  July  1st.     The  larva?  are  to  be  found 

*  Species  of  Sphenophorus.  Family  Calandridce.  See  S.  A.  Forbes, 
23d  Report  of  the  State  Entomologist  of  Illinois. 


176         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

during  July,  becoming  full  grown  and  pupating  during  the  latter 
part  of  that  month.  The  larvae  will  eat  out  quite  a  cavity  in  the 
interior  of  the  stalk  or  bulb,  and  then  attack  the  roots,  thus  often 
killing  a  whole  clump  or  stool  of  small  grain  or  timothy.  The 
pupal  stage  is  passed  in  a  small  cell  in  the  earth  and  lasts  from  two 


P'iG.  129. — Sphenophorus  ochreus,  larva,  aduh,  and  work  in  roots  of  Scirpiis. 
(After  F.  M.  Webster,  "Insect  Life.") 


to  three  weeks,  adult  beetles  emerging  from  the  middle  of  August 
to  the  first  of  October. 

One  of  the  most  injurious  species  to  corn  is  S.  ochreus  Lee. 
The  life  history  is  much  the  same  as  that  of  S.  parvulus,  though 
eggs  have  been  found  as  late  as  July  30th.  The  natural  food-plant 
of  this  species,  however,  is  the  common  club-rush  (Scirpus  fluvia- 
tilis),  the  roots  of  which  consist  of  bulbs  connected  by  smaller 
slender  roots.  The  eggs  are  deposited  in  or  about  the  roots  of  this 
rush,  never  having  been  found  on  corn.  The  bulbs  of  the  rush  are 
very  hard  and  oftentimes  as  large  as  hens'  eggs.     In  them  the 


INSECTS  INJURIOUS  TO  CORN 


177 


larvae  burrow,  becoming  full  grown  and  transforming  to  pupae, 
from  which  the  adult  beetles  appear  in  August  and  September. 
When  the  rush  l^ecomes  too  hard  for  the  beetles  they  often  attack 
a  common   reed    (Phragmites  comtnunis),   piercing  and  splitting 


Fig.  130. — Sections  of  sugar-cane  showing  work  of  Sphenophorus  obscurus: 
a,  larva;  b,  pupa;  c,  probable  points  of  oviposition.  (.\fter  Riley  and 
Howard,  "  Insect  Life.") 

lengthwise  the  unfolded  terminal  leaves,  and  eating  out  the  suc- 
culent portions  within.  The  injury  to  corn  is  done  by  the  beetles 
while  the  corn  is  still  young,  feeding  upon  it  in  the  same  manner 
as  do  the  other  species.  "  Standing  with  the  head  downward  and 
the  feet  embracing  the  lower  part  of  the  stalk,"  says  Dr.  Forbes, 
"  they  slowly  sink  the  beak  into  the  plant,  using  the  jaws  to  make 


178         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  necessary  perforation.  By  moving  forward  and  backward 
and  twisting  to  the  right  and  left,  the  beetle  will  often  hollow  out  a 
cavity  beneath  the  surface  much  larger  than  the  superficial  injury 
will  indicate."  As  the  lower  part  of  the  stalk  becomes  hardened, 
they  leave  it  for  the  terminal  portion,  and  when  the  ears  commence 
to  form  the}'  often  penetrate  the  husk  and  gorge  out  the  soft  cob. 
Sometimes  the  injury  thus  inflicted  is  but  slight,  merely  resulting 
in  a  puncturing  of  the  leaves  when  they  unfold,  these  holes  being 
in  a  series  across  the  leaf  resulting  from  a  single  puncture  when  the 
leaf  was  folded,  and  looking  much  like  the  work  of  the  corn-root 
webworm;  but  when  several  beetles  attack  a  young  plant,  they 
will  either  kill  it  outright  or  so  deform  the  foliage  and  stalk  that 
no  ear  will  mature. 

Several  other  species  have  also  been  known  to  do  more  or  less 
injury  to  corn,  viz.,  S.  scoparius,  placidus,  cariosus,  sculptilis, 
and  pertinax,  but  so  far  as  known  their  habits  and  injuries  are 
much  the  same  as  of  those  already  described. 

Means  of  Control. — The  control  of  these  pests  is  rather  a  diffi- 
cult task.  S.  ockreus,  as  in  fact  are  all  of  the  species,  is  most 
injurious  on  recently  cleared  swamp-lands,  and  usually  disappears 
as  fast  as  these  lands  are  drained  and  cultivated.  Planting  flax, 
potatoes,  or  some  crop  not  attacked  by  these  insects  for  the  first 
crop  will  largely  prevent  so  serious  injury  to  a  subsequent  corn 
crop.  The  burning  over  of  grass-  and  swamp-lands  infested  with 
the  beetles  will  also  be  of  considerable  value. 

The  Maize  Bill-bug  * 

Throughout  the  Southern  States  and  northward  to  Kansas 
there  has  been  more  or  less  serious  injury  by  a  bill-bug  which  has 
been  recognized  for  many  years  as  Sphenophorus  robustus  Horn, 
Recently  Dr.  F.  H.  Chittenden  has  recognized  this  insect  as  a  new 
species  and  Mr.  E.  O.  G.  Kelly  has  published  a  complete  account  of 
its  life  history,  from  which  the  following  is  taken. 

As  will  be  seen  below  this  species  is  known  to  pass  its  entire  life 

*  Sphenophorus  maidis  Chittn.,  see  E.  O.  G.  Kelly,  Bulletin  95,  Part  II, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  CORN 


179 


history  upon  the  coni-pUint,  so  that  the  common  name  given  it 
appropriately  distinguishes  it  from  the  other  bill-bugs  previously 
mentioned.  It  has,  however,  been  found  feeding  and  probably 
breeding  in  swamp-grass  (Tripsacuni  dactyloides),  which  may  be 
its  native  food  plant. 

Life  History. — The  eggs  were  found  in  southern  Kansas  during 
June,  laid  in  punctures  made  by  the  female  in  }'oung  corn-  plants. 
These  egg  punctures  are  mere  slits 
and  do  not  seem  to  materially  injure 
the  plant.  The  eggs  hatch  in  from 
seven  to  twelve  days,  and  from 
them  emerge  small  footless,  dingy 
white  grubs,  with  chestnut-l^rown 
heads,  of  the  appearance  shown 
in  Fig.  132.  "  They  at  once  begin 
feeding  on  the  tissues  of  the  voung 


corn 


at    the    l)ottom    of    the  egg 


Fig.  131. — The  maize  bill-bug 
{Sphenophorus  maidis  Chittn.) 
— four  tinges  natural  size. 
(After  Kehy,  U.  S.  Dept.  Agr.) 


puncture,  directing  their  burrow 
inward  and  downward  into  the  tap- 
root. When  they  finish  eating  the 
tender  parts  of  the  taproot  they 
direct  their  feeding  upwartl,  con- 
tinuing until  full  grown,  allowing 
thelower  portion  of  the  burrow  to 
catch  the  frass  and  excrement. 
This  burrowing  of  the  taproot  of  the 

young  growing  corn-plant  is  disastrous  to  the  root  system;  .  .  . 
allowing  it  to  die  or  become  more  or  less  dwarfed."  Often  the 
young  larvae  burrow  into  the  heart  of  the  plant  and  cut  off 
the  growing  bud,  thus  killing  the  top.  The  larvae  become  full 
grown  early  in  August,  when  they  are  about  four-fifths  of  an  inch 
long.  ''  The  lar\'ip,  on  finishing  their  growth,  descend  to  the  lower 
part  of  the  burrow,  to  the  crown  of  the  taproot,  cutting  the  pith 
of  the  cornstalk  into  fine  shreds,  with  which  they  construct  a  cell 
where  they  inclose  themselves  for  pupation."  The  pupae  are  to 
be  fountl  in  these  cells  in  late  August  and  early  September,  the 


180        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


pupal  stage  lasting  ten  to  twelve  clays.     The  adults  commence  to 

emerge  by  the  middle  of  August  and  continue  to  do  so  until  the 

middle  of  September.     "  Some  of  them  leave  the  pupal  cells,  but 

most    of   them    remain  there 

for    hibernation."        Those 

which     emerged    disappeared 

and    probably    hibernated   in 

some  dense,  coarse  grass  near 

by.     Those  which  hibernated 

in  the  pupal  cells  emerged  the 

next   spring   about   the   time 

that  young  corn  was  sprouting. 

The  beetles  are  from  two-fifths 

to  three-fifths  of  an  inch  long, 

of  a  dull  shining  black  color, 

and  sculptured  as  shown  in  Fig. 

131.     "  The  beetles  are  rarely 

observed  on  account  of  their 


Fig.  132. — Larva  of  the  maize  bill- 
bug — twice  natural  size.  (After 
Kelly,  U.  S.  Dept.  Agr.) 


Fig.  133. — C'om  plant  sho\\ang  the 
result  of  attack  of  the  maize  bill- 
bug:  a,  larval  burrow  containing 
pupa  in  natural  position — reduced 
two-thirds;  b,  egg-puncture  con- 
taining egg  —  enlarged.  (After 
Kelly,  U.  S.  Dept.  Agr.) 


quiet  habits  and  because  they  are  covered  with  mud — a  condition 
which  is  more  or  less  common  among  several  species  of  this  genus 
and  which  is  caused  by  a  waxy  exudation  of  the  elytra  to  which  the 
soil  adheres.  The  presence  of  the  adults  of  this  species  in  a  corn- 
field is  made  evident  by  the  withering  of  the  top  leaves  of  very 


INSECTS  INJURIOUS  TO  CORN  181 

young  corn-plants,  the  plants  having  been  severely  gouged. 
After  the  plants  grow  10  to  15  inches  tall  they  do  not  kill  them, 
but  gouge  out  such  large  cavities  in  the  stalks  that  they  become 
twisted  into  all  sorts  of  shapes.  The  attacked  plants  sucker  pro- 
fusely, affording  the  3'oung,  tender  growth  for  the  beetles  to  feed 
upon,  even  for  many  days  after  the  non-infested  plants  have 
become  hard."  Injury  seems  to  be  most  serious  on  low  land. 
Injury  by  this  species  somewhat  resembles  that  done  by  the  larger 
corn  stalk-borer  (Diatraea  zeacolella),  but  is  easily  distinguished 
from  the  work  of  the  other  bill-bugs,  as  the  punctures  of  the  latter, 
which  usually  form  a  row  or  rows  of  holes  in  the  leaves  when  they 
unfold,  are  not  always  fatal  to  the  plants. 

Control. — -Inasmuch  as  most  of  the  beetles  hibernate  in  the 
corn  stubble,  they  may  ))c  readily  destroyed  by  pulling  out  and 
Inirning  the  stuljble.  Care  must  be  taken,  however,  to  pull  out 
the  taproot,  as  the  stalk  will  be  liable  to  break  above  the  beetle 
and  leave  it  in  the  ground.  As  the  infested  stalks  have  a  poor 
root  system,  they  arc  easily  pulled. 

The  Corn  Ear-worm  * 

Practically  the  only  insect  injuring  the  ears  of  field-corn  and 
the  worst  insect  pest  of  sugar-corn,  is  the  ear-worm.  In  the 
extreme  South  it  is  almost  impossible  to  grow  sugar-corn  success- 
fully on  account  of  its  injury,  while  further  north  it  largely  reduces 
the  profits  of  corn  grown  for  the  cannery,  and  destroys  a  consider- 
able percentage  of  the  kernels  of  field-corn.  It  is  a  most  cosmopol- 
itan insect,  being  found  throughout  the  United  States  and  in  many 
parts  of  the  world,  and  has  a  long  list  of  food  plants,  being  known 
as  the  tomato  fruit-worm,  tobacco  bud-worm,  and  cotton  boll- 
worm  (see  pages  304,  234,  254)  when  attacking  these  plants, 
besides  which  it  feeds  on  beans,  peas,  and  many  garden  crops 
and  forage  plants,  such  as  cowpeas  and  alfalfa. 

Life  History. — Along  the  Gulf  Coast  the  first  moths  appear  in 
April,  in  the  latitude  of  33°  about  the  middle  of  May,  and  in  the 
latitude  of  Delaware  and  Kansas,  early  in  June. 

*  Heliothis  obsoleta  Fab.     Family  Noctuidce. 


182         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  moth  is  about  three-quarters  of  an  inch  long  with  a  wing 
expanse  of  about  If  inches  and  is  extremely  variable  in  color  and 
markings.  Some  are  dull  olive  green  while  others  are  yellowish 
or  nearly  white  and  with  almost  no  markings.  In  the  most  typical 
moths  the  wings  are  l^ordcred  with  dark  l^ands,  the  wing  veins  are 
black  and  the  fore-wings  are  spotted  with  l)lack. 


Fig.  134. — Corn  ear-worms  at  work.  The  central  cob  has  lieen  attacked  l)y 
a  nearly  full-grown  worm,  which  has  bored  through  the  husk  near  the 
middle. 


The  eggs  are  semispherical  in  shape,  al)out  one-fifteenth  inch  in 
diameter,  light  yellowish,  antl  prettily  corrugated  with  ridges  as 
shown  in  Fig.  184,  Those  of  the  first  brood  ai'e  laid  on  corn,  peas, 
beans,  or  whatever  food-plants  are  available,  and  liatcli  in  three  to 
five  days,  depending  upon  the  temperature. 

The  catei'pillars  of  the  first  generation  often  attack  corn  when 
about  knee-high,  feeding  in  the  axils  of  the  tender  leaves,  so  that 


INSECTS   INJURIOUS  TO  CORN 


183 


when  tlio  leaves  unroll  tluy  bear  horizontal  rows  of  holes.  The 
caterpillars  are  exceedingly  varial)le  in  color,  being  from  a  light 
green  through  rose  color  and  l)rown  to  almost  l)lack,  and  either 


Fig.  13.5. — Corn  ear-worm.     Iln.sk  of  ear  of  sugar-corn  torn  open,  showing 
worms  at  work  on  tip  and  hole  through  which  a  full  grown  worni  has  left. 

striped,  spotted  or  perfectly  plain.  The}-  become  full  grown  in 
about  2^  weeks  and  are  then  about  1^  to  Ih  inches  long.  When 
done  feeeding  the  caterpillar  burrows  2  to  5  inches  into  the  soil 
near  the  base  of  the  plant.  A  cell  is  then  constructed  wdiich  runs 
back  to  within  a  half  inch  of  the  surface  of  the  soil,  so  that  the 


184         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

moth  may  readily  push  off  this  surface  soil  and  escape.  The 
burrow  finished,  the  larva  retires  to  the  bottom  of  the  cell  and 
there  molts  and  enters  the  pupal  stage. 

The  pupa  is  four-fifths  inch  long,  shining  reddish-brown. 
During  the  summer  the  moths  emerge  about  two  weeks  later, 
but  the  last  generation  in  the  fall  passes  the  winter  in  the  pupal 
stage.  Thus  the  complete  life  cycle  from  egg  to  adult  moth 
requires  slightly  over  a  month  in  midsummer,  and  from  six  to 
eight  weeks  for  the  spring  and  fall  broods. 

The  second  generation  of  moths  appears  a])out  the  middle 
of  July  in  the  latitude  of  Delaware  and  Kansas.  In  the  far 
South  the  second  generation  of  moths  appears  when  corn  is  com- 
ing into  silk  and  tassel,  upon  which  the  moths  always  prefer  to 
lay  their  eggs.  As  a  result,  the  caterpillars  of  the  second  genera- 
tion in  the  South,  and  the  third  further  North,  do  serious  injury 
to  field-corn,  gnawing  out  the  kernels  at  the  tips  of  the  ears,  and 
furnishing  favorable  conditions  for  molds  to  propagate,  which 
do  further  injury.  From  2  to  3  per  cent  of  the  corn  crop  of  the 
country,  with  a  cash  value  of  $30,000,000  to  $50,000,000,  is  thus 
destroyed  by  the  ear  worm  annually. 

The  third  generation  of  moths  appears  the  last  of  August 
in  Delaware  and  Kansas  and  gives  rise  to  the  third  brood  of 
caterpillars,  which  are  there  the  most  destructive  brood  on  field- 
corn  and  sugar-corn,  frequently  causing  a  loss  of  from  10  to  50 
per  cent  of  the  latter  crop.  The  caterpillars  become  full  grown 
during  the  latter  part  of  September  and  change  to  pupse,  which 
hibernate  over  winter  as  already  described. 

In  the  Gulf  States  there  arc  four  full  broods  and  along  the 
Gulf  Coast  there  may  be  five  or  six,  while  in  the  Northern  States 
there  are  but  two  generations,  with  possibly  but  one  in  Ontario. 

Control. — As  the  pupa?  pass  the  winter  in  the  soil,  by  all  means 
the  most  satisfactory  and  practical  means  of  control  is  to  plow 
infested  land  in  late  fall  or  during  the  winter,  plowing  deeply 
and  harrowing.  This  will  break  up  the  pupal  cells,  crush  some 
of  the  pupae,  and  expose  others  to  the  rigors  of  winter  to  which 
most  of  them  will  succumb. 


INSECTS  INJURIOUS  TO  CORN  185 

The  early  planting  of  field-corn  prevents  the  moths  from  lay- 
ing their  eggs  upon  it,  as  it  will  have  passed  the  silking  stage  and 
other  fields  which  are  in  silk  will  be  preferred;  it  being  possible 
to  thus  reduce  the  injury  by  at  least  a  third  by  early  planting. 

Where  the  caterpillars  of  the  first  generation  are  working  in 
the  unfolding  leaves,  they  are  sometimes  poisoned  with  Paris 
green,  mixed  with  flour  or  corn  meal  as  used  for  this  pest  on 
tobacco,  but  as  Paris  green  often  burns  the  foliage  powdered 
arsenate  of  lead  will  doubtless  be  found  equally  effective  with- 
out burning. 


CHAPTER  X 

INSECTS   INJURIOUS   TO   STORED   GRAINS* 

The  farmer  who  stores  his  grain,  awaiting  a  higher  price, 
is  sometimes  sadly  disappointed  to  find  that  it  has  been  so 
riddled  by  "  weevil  "  that  it  brings  no  more  than  had  it  l)een  sold 
previously. 

The  term  "  weevil  "  is  rather  a  comprehensive  one,  being 
commonly  applied  to  almost  every  ins(^ct  inf(\sting  stored  food- 
products.  Only  a  few  species  are  commonly  injurious  in  the 
farm-granary. 

(jrain-weevils 

Of  these  the  Granary-weevil  f  and  the  Rice-weevil  J  (Fig. 
136),  are  the  most  common  and  widely  distributed.  Both  of 
these  insects  have  infested  grain  from  the  most  ancient  times,  so 
long,  in  fact,  that  the  granary-weevil  has  lost  the  use  of  its  wings 
and  remains  entirely  indoors.  They  are  small,  brown  beetles, 
from  one-eighth  to  one-sixth  of  an  inch  in  length,  with  long  snouts 
which  are  of  great  service  in  boring  into  the  kernels  of  grain. 
By  means  of  them  the  females  puncture  the  grain  and  then  insert 
an  egg  in  the  cavity.  The  larva  hatching  from  this  is  without 
legs,  somewhat  shorter  than  the  adult,  white  in  color,  and  of  a 
very  robust  build,  being  almost  as  broad  as  long.  It  soon  devours 
the  soft  interior  of  the  kernel  and  then  changes  to  a  pupa,  from 
which  the  adult  beetle  emerges  in  about  six  wrecks  from  the 
time  the  egg  was  laid. 

Only  a  single  larva  inhabits  a  kernel  of  wheat,  but  several 

*  See   "  Some   Insects   Injurious  to  Stored   Grains,"   F.   H.   Chittenden, 
Farmers'  Bulletin,  45,  U.  S.  Department  of  Agriculture. 
f  Calandra  granaria  Linn. 
X  Calandra  oryzce  Linn.     Family  Calandridce. 

186 


INSECTS  INJURIOUS  TO  STORED   GRAINS 


187 


will  often  be  found  in  that  of  corn.  Not  only  do  the  larvcc 
injure  the  grain,  but  the  beetles  feed  upon  it,  and  then  hollow 
out  a  shelter  for  themselves  within  the  hull.  The  beetles  are 
quite  long-lived,  and  thus  do  considerable  damage.  The  egg- 
laying  period  is  equally  long,  and  as  there  are  three  or  four  broods 
in  the  North  and  six  or  more  in  the  South,  it  has  bqpn  estimated 
that  the  progeny  of  one  pair  would  amount  to  6000  Insects  in  a 
single  season. 

Grain-beetles 

Another  beetle  very  common  in  the  granary,  l)ut  of  cjuite 
different  appearance,  is  the  Saw-tooth(>d  (Jrain-l^eetle  *  (Fig.  137). 
It  is  a  cosmopolitan 
pest  and  is  also  nearly 
omnivorous.  The 
beetle  is  only  about 
one-tenth  of  an  inch 
long,  ver}"  much  flat- 
tened, of  a  dark-l^rown 
color,  and  may  be 
easily  recognized  by 
the  six  saw-like  teeth 
on  each  side  of  the 
thorax.  The  larva  is 
of  a  dirty-white  color, 
and  quite  dissimilar 
from  that  of  the  gra- 
nary weevil.  Having 
six  legs  to  carry  it 
about,  it  is  not  satisfied 
with  a  single  seed,  but 
runs    about  here  and 

there,  nibbling  at  several.  When  full  grown  the  larva  glues  together 
several  grains  or  fragments  into  a  little  case,  and  inside  of  this  trans- 
forms to  the  pupa  and  then  to  the  beetle.    In  early  spring  this  life 

'''  Silvanus  surinamensis  Linn.     Family  Cucujidm. 


Fig.  136. — The  grain  weevil  (Calandra  granarin) : 
a,  beetle;  b,  larva;  c,  pupa,  d,  the  rice  weevil 
(('.  oryza) :  jjeetle — all  enlarged.  (After  Chit- 
tenden; U.  S.  Dept.  Agr.) 


188      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

cycle  requires  from  six  to  ten  weeks,  but  in  summer  it  is  reduced 
to  about  twenty-five  days.  Thus  there  are  from  three  to  six 
or  more  generations  during  a  season,  according  to  the  latitude. 
The  Red  or  Square-necked  Grain-beetle  *  is  about  the  same 
size  as  the  last  species,  but  is  of  a  reddish-brown  color,  and  the 
thorax  is  almost  square,  nearly  as  broad  as  the  abdomen,  and 
not  notched  on  the  sides.  It  breeds  in  corn  in  the  field  and  in 
the  granary,   first  destroying  the  germ,  so  that  it  is  especially 


Fig.  137. — The  saw-toothed  grain  ])eetle  (Silvanus  surinamensis):  a,  adult 
beetle;  b,  pupa;  c,  larva — all  enlarged;  d,  antenna  of  larva — still  more 
enlarged;  d,  the  red  or  square-necked  grain  beetle  {Cathartus  gemellatus 
Duv.)      (After  Chittenden,  U.  S.  Dept.  Agr.) 


injurious  to  seed-corn.  It  feeds  mostly  out  of  doors,  though 
sometimes  infesting  the  granary. 

The  Foreign  Grain-beetle  f  is  of  much  the  same  general 
appearance,  but  smaller  and  of  a  more  robust  appearance  It 
feeds  upon  a  great  variety  of  stored  products  as  well  as  grain, 
but  rarely  becomes  troublesome. 

The  Cadelle  %  also  has  the  bad  habit  of  first  attacking  the 
embryo  or  germ  of  the  kernel,  and  going  from  one  kernel  to  another, 
thus   destroys   a   large    numljer  for  seed  purposes.     It  possesses, 

*  Cathartus  gemellatus  Duv. 

t  Cathartus  advena  Waltl. 

X  Tenebroides  maurilanicas  Linn.     Family  TrogosUulce. 


INSECTS   INJURIOUS  TO  STORED  GRAINS 


189 


however,  the  good  trait  of  feeding  on  other  injurious  grain- 
insects.  The  beetle  is  ol)long,  flat,  nearly  l)la('k,  and  about 
one-third  of  an  inch  long.     The  larva  is  of  a  whitish  color,  with  a 


\  V 


Fig.  138. — TheCadelle  (Tenebroides  mauritanicus) :  a,  adult  beetle  with  greatly 
enlarged  antenna  above;  h,  pupa;  c,  larva — all  enlarged.  (After 
Chittenden,  U.  S.  Dept.  Agr.) 

brown  head,  the  thoracic  segments  are  marked  with  brown,  and 
the  abdomen  terminates  in  two  dark  horny  processes.  It  is  a 
fleshy  grub,  nearly  three-fourths  of  an  inch  long  when  full  grown. 

Flour-  and  Meal-moths 

The  larv»  of  several  small  moths  sometimes  infest  grain 
in  store,  but  rarely  do  it  serious  damage,  preferring  the  softer 
flour^  meal,  and  food-products. 

The  most  destructive  of  these  is  the  Mediterranean  Flour- 


190 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


moth  *  (Fig.  139) .  This  insect  was  practically  unknown  until 
1877,  but  during  recent  years  it  has  occasioned  the  loss  of  many 
thousands    of    dollars    to    mill-owners.     It    occurs    throughout 


Fig.  139. — The  Mediterranean  flour-moth  (Ephestia  kuehnictta):  a,  moth;  6, 
same  from  side,  resting;  c,  larva;  d,  pupa — enlarged;  e,  abdominal  joint 
of  larva — more  enlarged;  /,  larva,  dorsal  view.  (After  Chittenden 
U.  S.  Dept.  Agr.) 


Fig.  140. — The  Indian  meal-moth  {Plodia  inter punctella):  a,  moth;  b,  pupa; 
c,  caterpillar;  /,  same,  dorsal  view — somewhat  enlarged;  d,  head,  and  e, 
first  abdominal  segment  o.f  caterpillar — more  enlarged.  (After  Chitten- 
den, U.  S.  Dept.  Agr.) 

Europe,  and  is  found  in  Mexico  and  Chili.  It  was  first  recognized 
in  America  in  1SS9,  and  has  since  done  an  increasing  amount 
of  damage  in  California,  in  New  York  and  Pennsylvania,  North 
Carolina,  Alabama,  New  Mexico,  and  Colorado,  and  has  become 

*  Ephestia  kuehniella  Zell.  Family  Pyralidce.  See  W.  G.  Johnson, 
Appendix  19th  Report  State  Entomologist  of  Illinois,  and  F.  L.  Wa.shburn, 
Special  Report  of  the  State  Entomologist  of  Minnesota  on  the  Mediter- 
ranean flour-moth. 


INSECTS  INJURIOUS  TO  STORED  GRAINS 


191 


quite  generally  distributed.  "  The  caterpillars  form  cylindrical 
silken  tubes  in  which  they  feed,  and  it  is  in  great  part  their  habit 
of  web-spinning  that  renders  them  so  injurious  where  they  ol)tain 
a  foothold.  Upon  attaining  full  growth  the  caterpillar  leaves 
its  original  silken  domicile  and  forms  a  new  web,  which  becomes 
a  cocoon  in  which  to  undergo  its  transformations  to  pupa  and 
imago.  It  is  while  searching  for  a  suitable  place  for  transforma- 
tion that  the  insect  is  most  troublesome.  The  infested  flour 
becomes  felted  together  and  lumpy,  the  machinery  becomes 
clogged,  necessitating  frequent  and  prolonged  stoppage,  and  result^ 
ing  in  a  short  time  in  the  loss  of  thousands  of  dollars  in  large 
establishments." 

The  life  cycle  of 
this  insect  requires 
ordinarily  about 
two  months,  but 
may  be  completed 
in  thirty-eight  days 
u  n  d  e  r  the  most 
favorable  condi- 
tions. The  adult 
moth  measures  a 
little  less  than  an 

inch  across  the  expanded  wings.  The  fore-wings  are  of  a  lead- 
gray  color,  with  transverse  black  markings,  while  the  hind- 
wings  are  dirty  whitish,  with  a  darker  Ijorder. 

The  Indian  Meal-moth  *  (Fig.  140)  larvae  resemble  those  of 
the  grain-beetles  in  having  a  special  liking  for  the  embryo  of 
wheat-grains.  They  spin  a  fine  silken  web  as  they  go  from  seed 
to  seed,  to  which  they  become  attached,  and  to  which  is  added  a 
large  amount  of  excrement,  thus  spoiling  for  food  much  more 
grain  than  is  actually  injured. 

The  moth  has  a  wing-expanse  of  an  inch;  the  inner  third 
of  the  fore-wings  being  a  whitish  gray,  and  the  outer  portion 
reddish-l)rown,  with  a  coppery  lustr(\ 

*  Plodia  inter punctella  Hbn.     Family  PuiulidcB. 


Fig.  141. — The  meal  snout-moth  (Pyralis  farinali^) : 
a,  adult  moth;  b.  larva ;c,  pupa  in  cocoon — twice 
natural  size.     (After  Chittenden,  U.  S.  D.  Agr.) 


192        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Meal  Snout-moth  *  (Fig.  141)  is  of  a  light  brown  color, 
the  thorax,  base,  and  tips  of  the  fore-wings  being  darker  brown. 
The  wings  expand  nearly  an  inch  and  are  otherwise  marked 
with  whitish  lines  as  shown  in  the  figu-re.  It  is  very  similar  to 
the  last-mentioned  species  in  its  habits,  constructing  long  tubes 
with  silk  and  particles  of  the  food  in  which  it  is  living.  The  life- 
history  is  completed  in  about  eight  weeks,  and  four  generations 
may  oc-cur  in  a  year.  The  moisture  of  "  heated  "  grain  is  most 
favorable  for  the  development  of  this  pest,  and  it  need  not  be 
feared  if  grain  is  kept  in  a  clean,  dry  place. 

The  Angoumois  Grain-moth  f 

By  far  the  worst  granary  pest  throughout  the  South  is  the 
"  fly-weevil,"  or  Angoumois  grain-moth. 

History. — This  insect  is  an  importation  from  Europe  and  receives 
its  name  from  the  fact  that  in  1760  it  "  was  found  to  swarm  in  all 
the  wheat-fields  and  granaries  of  Angoumois  and  of  the  neighbor- 
ing provinces  [of  France],  the  afflicted  inhabitants  being  thereby 
deprived  of  their  principal  staple,  and  threatened  with  famine 
and  pestilence  from  want  of  wholesome  bread."  The  insect 
was  first  noted  in  this  country  in  North  Carolina  in  1730,  and  in 
1796  was  so  abundant  as  to  extinguish  a  lighted  candle  when  a 
granary  was  entered  at  night.  It  is  essentially  a  southern  insect, 
being  very  injurious  to  stored  corn  in  the  (lulf  States.  Of  late 
years  it  seems  to  be  moving  steadily  northward,  being  reported 
as  injurious  in  central  Pennsylvania  and  Ohio.  Wheat,  corn, 
oats,  rye,  barley,  sorghum-seed,  and  even  cow-peas  are  subject 
to  injury. 

Life  History. — The  injury  is  not  done  by  the  moth,  as  might 
be  reasonably  supposed  from  the  fact  that  it  is  the  only  form  of 
the  insect  usually-  seen,  but  is  done  by  the  small  caterpillars 
which  feed  within  the  grain,  where  they  may  be  found  during 
the  winter.  The  caterpillar  eats  to  the  surface  of  the  kernel, 
but  not  through  it,  thus  leaving  a  thin  lid  which  the  moth  can 

*  Pyralis  farinalis  Linn.     Family  Pyralidcc. 
t  Sitotroga  cerealella  Oliv.     Family  Gelechiidce. 


INSECTS  INJURIOUS  TO  STORED  GRAINS 


193 


easily  push  aside  when  it  comes  out  in  the  spring,  and  then  covers 
itself  with  a  fine  silken  \Tvh.  At  this  time  the  caterpillar  is 
usually  fully  grown  and  is  about  one-fifth  of  an  inch  long,  of  a  white 
color,  with  the  head  yellowish  and  harder,  and  having  six  jointed 
legs  in  front,  a  series  of  four  pairs  of  fleshy  pro-legs  along  the 
middle,  and  another  pair  of  soft  legs  at  the  end  of  the  body. 
With  warm  spring  weather  the  caterpillar  changes  to  a  pupa 
and  about  the  time  that  the  Avheat  comes  into  head  the  adult 
moth  emerges.     As  soon  as  it  emerges,  whether  outdoors  or  in  a 


Fig.  142. — The  Angoumois grain-moth  (^/to^rof/a  ccrcaldln):  o,  eggs;  b,  larva 
at  work;  c,  larva,  side  view;  d,  pupa;  c,  moth;  /,  same,  side  view. 
(After  Cliittenden,  U.  S.  Dept.  Agr.) 


barn,  the  moth  at  once  flies  to  the  grain-field,  where  the  eggs  are 
deposited.  The  exact  time  at  which  the  moths  emerge  varies, 
but  occurs  some  time  late  in  May  or  in  June.  The  moths  quite 
closely  resemble  the  clothes-moth  often  foimd  flying  about  houses. 
The  wings  are  quite  narrow,  and  when  expanded  measure  about 
one-half  an  inch  from  tip  to  tip,  being  of  a  yellowish  or  buff  color, 
marked  with  black.  The  eggs  are  laid  in  the  longitudinal  channel 
on  the  side  of  the  grain.  Each  female  lays  from  sixty  to  ninety 
eggs  in  lots  of  about  twenty  each,  one  lot  thus  being  about  enough 
to  infest  the  kernels  of  a  head.  The  eggs  hatch  in  from  four  to 
seven  days.  The  young  caterpillars  are  at  first  very  active 
and  soon  find  tender  places  and  bore  into  the  kernels,  leaving 


194      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


almost     invisible     openings.      These     caterpillars    become    full 
^  grown    in    about    three    weeks,    just 

al)out    the  time  the  grain  is  mature, 
'^^^    '  il  About  harvest-time  the  second  brood 

tA  of  moths  appears.      These    lay  then' 

^sij  eggs  during  July,  depositing  them  on 

>■  the  ripe  heads  if  the  harvest  be  a  little 
S  delayed,  Ijut  on  the  wheat  in  stack  if 
S  harvest  is  prompt.  Usually  the 
flTo^'^^l  tS  caterpillars  hatching  from  these  eggs 
become  full  grown  and  remain  in  the 
s"^^  2  grain  over  winter,  but  in  warm  sea- 
sons, especially  if  warm  in  September 
or  when  the  pest  is  unusually  abun- 
dant, a  third  brood  of  moths  appears 
early  in  September.  These  lay  another 
batch  of  eggs  about  the  middle  of 
September,  depositing  them  upon  the 
open  ends  of  grain  in  stack  or  mow, 
which  thus  becomes  more  infested  than 
that  in  the  centre.  In  grain  stacked 
outside,  the  caterpillars  of  this  brood 
become  full  grown  slowly  and  remain 
in  the  grain  over  winter,  but  if  in 
the  barn  they  grow  faster  and  a 
fourth  brood  of  moths  appears  about 
the  middle  of  October,  the  moths  being 
noticed  in  threshing.  The  insects  con- 
tinue to  breed  within  doors  all  winter 
as  long  as  any  grain  remains,  though 
they  become  sluggish  and  cease  feed- 
ing during  cold  weather.  The  number 
of  broods  is  entirely  dependent  upon 
the  latitude  and  weather  conditions; 
in  the  South,  where  they  can  breed 
continuously,  there  l)cing  as  many  as  eight  in  a  year. 


bC 


•g 


'M. 


H 


INSECTS  INJURIOUS  TO  STORED  GRAINS  195 

Corn  is  frequently  attacked,  Ijut  not  until  it  is  ripe  and  husked, 
and  then  but  rarely  when  husked  in  October  and  November  and 
stored  outdoors  in  slatted  cribs.  Seed-corn  stored  in  barns,  and 
in  the  South  in  almost  any  situation,  is  often  badly  injured. 

Aside  from  the  loss  in  weight,  grain  when  badl}-  infested 
becomes  unfit  for  milling  purposes,  and  will  even  be  refused  l)y 
cattle  and  horses,  which  should  not  be  urged  to  eat  it,  though 
hogs  and  fowls  will  readily  consume  it. 

Remedies. — Dr.  J.  B.  Smith,  in  an  interesting  bulletin  upon 
this  pest,  to  which  we  are  indebted  for  much  of  the  above,  advises 
as  follows:  "  Thresh  as  soon  after  harvest  as  possible,  and  bulk  in 
tight  bins  or  in  good  sacks.  [By  "  tight  bins  "  are  meant  those 
which  will  not  permit  the  entrance  or  exit  of  the  moths.]  If  the 
grain  is  dry  when  harvested,  it  may  be  threshed  at  once;  if  not,  as 
soon  as  it  is  in  good  condition.  If  the  sacked  grain  is  infested, 
there  will  not  be  wormy  kernels  sufficient  to  heat  the  grain.  The 
moths  cannot  make  their  way  out  and  are  stifled.  Nothing  can 
come  in  from  outside  and  the  grain  remains  safe.  The  threshing 
itself  kills  many  of  the  insects  and  jars  and  rubs  off  many  of  the 
eggs.  If  binned,  the  bins  should  be  tight  and  the  grain  should  be 
tested  occasionally  for  any  appreciable  heating.  If  it  heats  per- 
ceptil)ly,  it  indicates  considerable  infestation,  and  it  should  be 
treated  with  carbon  bisulfide  at  once,  used  at  the  rate  of  one 
drachm  per  cubic  foot,  or  1  pound  for  250  cubic  feet  bin-space." 
Recent  investigations  have  shown  that  more  l)isulfide  will  often 
be  necessary.     See  page  198. 

Those  having  wheat  unthreshed,  whether  in  stack  or  mow, 
should  thresh  at  once,  and  treat  as  above  directed,  except  that  if 
much  of  it  is  noticed  to  be  wormy,  it  should  be  treated  with  carbon 
bisulfide  at  once,  as  soon  as  threshed,  which  if  done  thoroughly 
will  prevent  any  further  infestation  that  year. 

Barns  and  storehouses  should  he  cleaned  up  and  freed  from  all 
loose  and  scattered  grain — chickens  will  help  in  this — before  April 
1st,  so  that  no  moths  will  be  allowed  to  develop  and  infest  the 
grain  in  the  field.  Places  where  grain  has  been  in  shock  the  pre- 
vious season  should  be  cleaned  up  by  the  aid  of  chickens.     Thus  if 


190        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

there  is  any  probability  of  grain  being  infested,  it  should  be  kept 
tightly  covered  in  the  spring  so  as  not  to  permit  the  spread  of  the 
moths  to  the  fields. 

Prevention  of  "  Weevil  " 

Undoubtedly  grain-insects  can  usually  be  more  successfully 
combated  by  a  proper  housing  of  the  grain.  No  matter  how  often 
the  insects  are  destroyed  in  a  granary,  if  the  remainder  of  the  barn 
is  full  of  dust,  sweepings,  and  refuse,  as  it  generally  is,  on  which 
the  beetles  can  feed  and  in  which  they  will  breed,  and  if  the  gran- 
ary is  not  absolutely  tight,  as  soon  as  the  gas  passes  olT  the  insects 
from  the  barn  will  again  enter  the  granary,  and  soon  it  will  be  as 
badly  infested  as  ever. 

Cleanliness. — "  Cleanliness  will  accomplish  much  toward  the 
prevention  of  injury  from  these  pests,  the  cause  of  a  great  propor- 
tion of  injuries  in  granaries,  mills,  elevators,  and  other  structures 
where  grain  and  feed  are  stored  being  directly  traceal^le  to  a  dis- 
regard of  neatness.  Dust,  dirt,  rubbish,  and  refuse  material  con- 
taining sweepings  of  grain,  flour,  and  meal  are  too  frequently  per- 
mitted to  accumulate  and  serve  as  breeding-places  for  a  multitude 
of  injurious  insects. 

"  The  floors  or  corners  and  walls  of  the  l^arn  or  storehouse 
should  be  frequently  swept,  and  all  material  that  has  no  commer- 
cial value  burned." 

The  Granarij. — "  The  ideal  farmer's  granary,  from  the  stand- 
point of  insect  ravages,  should  be  built  at  some  distance  from 
other  buildings,  and  the  rooms  constructed  of  matched  floorings 
so  as  to  be  as  near  vermin-proof  as  possible.  The  doors  should  fit 
tightly,  closing  upon  a  raljl^et,  which  may  be  covered  with  felt  or 
packing,  and  the  windows  covered  with  frames  of  wire  gauze  to  pre- 
vent the  passage  of  insects.  The  floor,  walls,  and  ceilings  should 
be  smooth,  so  as  not  to  afford  any  lurking-places  for  the  insects, 
and  it  would  be  well  to  have  them  oiled,  painted,  or  whitewashed 
for  further  security.  A  coating  of  coal-tar  has  been  strongly  recom- 
mended for  the  latter  purpose." 

"  The  value  of  a  cool  place  as  a  respository  of  grain  has  been 


INSECTS   INJl'RIOUS  TO  STORED  GRAINS  197 

known  of  old,  and  a  building  in  which  any  artificial  heat  is 
cmplo}-cd  is  undesirable  for  grain  storage.  The  '  heating  '  and  fer- 
mentation of  grain,  as  is  well  known,  is  productive  of  '  weevil,'  and 
this  should  be  prevented  b}'  avoiding  moisture  and  by  ventilation- 
"  The  storage  of  grain  in  large  bulk  is  to  be  commended,  as  the 
surface  layers  only  are  exposed  to  infestation.  This  practice  is 
particularly  valuable  against  the  moths,  which  do  not  penetrate 
far  beneath  the  surface.  Frequent  agitation  of  the  grain  is  also 
destructive  to  the  moths,  as  they  are  unable  to  extricate  them- 
selves from  a  large  mass,  and  perish  in  the  attempt.  The  true 
granary-weevils  (small  dark-brown  beetles  with  long  curved 
snouts,  similar  to  the  pea-weevil),  however,  penetrate  more 
deepl}',  and  although  bidking  is  of  value  against  them,  it  is  not 
advisable  to  stir  the  grain,  as  it  merely  distributes  them  more 
thoroughlv  through  the  mass." — Chittenden. 


Destruction  of  "  Weevil  " 

Carbon  Bisuljide. — "  The  simplest,  most  effective,  and  most 
inexpensive  remedy  for  all  insects  that  affect  stored  grain  and 
other  stored  products  is  the  bisulfide  of  carbon,  a  colorless  liquid, 
with  a  strong  disagreeable  odor,  which,  however,  soon  passes 
away."  At  ordinary  temperatures  it  vaporizes  rapidly,  forming  a 
heavy  gas,  which  is  highly  inflammable  and  a  powerful  poison. 

Application. — It  may  be  applied  directly  to  the  infested  grain 
or  seed  without  injury  to  its  edibleness  or  viability  by  spraying 
with  an  ordinary  watering-can  having  a  fine  rose  nozzle.  In 
moderately  tight  bins  it  is  more  effective,  however,  as  it  evaporates 
more  slowly  and  diffuses  more  evenly,  if  placed  in  shallow  dishes 
or  pans,  or  on  bits  of  cloth  or  cotton  waste  distributed  about  on 
the  surface  of  the  grain  or  infested  material.  The  liquid  volatil- 
izes rapidly,  and,  being  heavier  than  air,  descends  and  permeates 
the  mass  of  grain,  killing  all  insects  and  other  vermin  present. 
The  bin  should  then  be  covered  with  boards,  canvas,  or  blankets, 
and  allowed  to  remain  at  least  twenty-four  hours.  If  to  be  used 
for  seed,  it  should  not  be  left  for  over  thirty-six  hours;  but  if  not, 


198         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

leave  it  forty-eight  hours,  which  will  do  it  no  injury  for  food. 
After  treating,  keep  the  grain  covered  to  prevent  reinfestation. 

A7yiount  to  Use. — It  was  formerly  recommended  that  the  l^isul- 
fide  be  applied  at  the  rate  of  1  to  3  pounds  to  100  l^ushels  of  grain 
or  1000  cubic  feet  of  open  space.  Recent  experiments,  however, 
have  shown  the  total  inadequacy  of  this  dosage.  Experiments 
made  by  Hinds  and  Hunter  *  show  that  the  effectiveness  of  the 
gas  is  in  direct  proportion  to  the  temperature.  Below  60°  F.  the 
fumigation  is  ineffective  and  inadvisable.  A  dosage  which  will 
kill  practically  all  the  weevil  at  67°  to  70°  will  kill  but  60  to  70  per 
cent  at  60°  to  65°.  They  recommend  the  use  of  5  pounds  per 
1000  cubic  feet  where  the  room  or  bin  is  quite  tight  and  the  tem- 
perature is  70°  or  alDOve.  For  loose  rooms  and  lower  tempera- 
tures, the  dosage  must  be  largely  increased  and  may  not  be  profit- 
al)le.  The  above  estimates  are  based  upon  the  grain  Ijeing  in  a 
cubical  shape;  if  it  is  spread  out  shallow,  more  bisulfide  will  be 
necessary. 

Caution. — "Certain  precautions  should  always  bie  oljscrved. 
The  vapor  of  carlion  bisulfide  is  deadly  to  all  forms  of  animal 
life  if  inhaled  in  sufficient  quantity,  l)ut  there  is  no  danger  in 
inhaling  a  small  amount.  The  vapor  is  highly  inflammable, 
but  with  proper  care  that  no  fire  of  any  kind,  as,  for  example, 
a  lighted  cigar,  lantern,  or  light  of  any  kind,  be  brought  into 
the  vicinity  until  the  fumes  have  entirely  passed  away,  no  trouble 
will  be  experienced." 

Hydrocyanic  Acid  Gas. — Mills  and  storehouses  which  needed 
treatment  were  formerly  fumigated  with  carbon  bisulfide,  which 
is  still  employed  to  a  considerable  extent,  l^ut  this  has  been 
largely  replaced  by  fumigation  with  hydrocyanic  acid  gas,  which 
obviates  the  risk  from  fire.  Directions  for  the  use  of  this  gas 
should  be  obtained  from  the  entomologist  of  the  State  experiment 
station  or  from  the  Bureau  of  Entomology  of  the  U.  S.  Depart- 
ment of  Agriculture. 

Sulfur  Fumes. — Professor  R.  I.  Smith   (l.c)  has  made  experi- 

*  Hinds  and  Hunter,  Journal  of  Economic  Entomology,  Vol.  Ill,  p.  47: 
R.  I.  Smith,  Bulletin  203,  N.  C.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  STORED  GRAINS  199 

nients  with  sulfur  dioxid;  produced  by  burning  sulfur  slightly  wet 
with  alcohol,  and  finds  that  it  will  effectively  kill  grain  insects 
but  injures  the  germinating  power  of  the  grain.  "  It  was  found  that 
the  fumes  produced  by  burning  2J  pounds  of  sulfur  either  in  a 
moist  or  dry  atmosphere  of  1000  cubic  feet  space,  for  twenty 
hours,  would  kill  all  exposed  adult  insects  and  practically  all  the 
young  stages  in  the  grain,  but  that  this  also  destroyed  its  germinat- 
ing power.  .  .  While  this  treatment  cannot  be  recommended 
for  general  fumigation,  there  is  no  doubt  of  its  being  the  easiest 
and  cheapest  method  of  fumigating  corn  cribs,  granaries  and 
similar  places  whenever  they  arc  being  cleaned  out  and  freed 
of  insects  in  preparation  for  the  reception  of  more  grain." 

Heat. — The  heating  of  grain  was  one  of  the  earliest  means 
known  of  comlmting  grain  insects,  but  has  been  little  used  in  this 
countr}'.  Recently,  however,  Mr.  Geo.  A.  Dean  of  the  Kansas 
Agricultural  Experiment  Station,*  has  shown  that  by  super- 
heating mills  they  may  be  rid  of  insect  pests  much  more  quickly 
and  cheapl}'  than  ]\\-  fumigation,  and  with  no  risk  from  fire,  or 
from  cyanide  poisoning.  His  experiments  show  that  if  the 
temperature  surrounding  an  insect  be  maintained  above  120°  F., 
with  a  normal  amount  of  moisture,  that  in  a  very  few  minutes  it 
will  be  killed.  This  promises  to  become  one  of  the  most  prac- 
ticable methods  of  cleaning  mills  and  may  be  used  for  small 
quantities  of  grain,  wlu^re  there  are  facilities  for  heating  it  or 
placing  it  in  a  superheated  room,  but  probably  carbon  bisulfide 
fumigation  will  be-  found  more  practicable  for  small  amounts. 
*  Geo.  A.  Dean,  Journal  of  Economic  Entomology,  Vol.  IV,  p.  142. 


CHAPTER  XI 

INSECTS  INJURIOUS  TO  CLOVER  * 

The  Clover  Root-borer  j 

The  clover  root-borer  is  practically  the  onty  insect  pest  which 
seriously  injures  clover  roots.  It  has  long  been  known  as  a 
clover  pest  in  Europe,  but  was  first  noticed  in  this  country  in 


Fig.  144.— The  clover  root-ljorer  {Hylastinufi  obscurus):  a,  adult,  natural 
size  at  right ;  b,  larva  or  grul);  c,  pupa — much  enlarged.  (After  Webster, 
U.  S.  Dept.  Agr.) 

western  New  York  in  1876,  whence  it  has  spread  southward  to 
West  Virginia  and  westward  to  Illinois  and  southern  Michigan, 
and  has  also  ])een  injurious  in  Oregon. 

Life  History. — During  the  winter  the  beetles  may  l:)e  found 
hibernating  in  their  ]:)urrows  in  infested  clover  roots.  They  are 
not  readily  distinguishal)le,  for  the}'  are  scarcely  one-eighth 
inch  long,  and  are  of  a  reddish-brown  color  much  like  that  of  the 
burrow.     With  the  warmer  weather  of  spring  they   commence 

*  See  The  Insect  Pests  of  Clover  and  Alfalfa,  J.  W.  Folsom,  25th  Report 
of  the  State  Entomologist  of  Illinois,  p.p.  41-124. 

t  Hylastinus  ohscuni-'i  Marsham.      Family  Scoly(id(g. 

200 


INSECTS  INJURIOUS  TO  CLOVER 


201 


burrowing  and  feeding  in  the  roots,  and  during  late  May  and  early 

June  the  females  deposit  their  eggs  along 

the  sides  of  the  tunnels.      "  The   female 

gouges  out  a  shallow  cavity,  more  often 

in  the  crown  of  the  plant,  sometimes  at 

the  sides  of  the  root  even  2  or  3  inches 

below   the    crown,    and   in   this   places, 

singly,  but  not  far    separated,  about    a 

half  dozen  pale  whitish,  elliptical,  very 

minute  eggs.      These   hatch  in  about  a 

week,  and  the  larvie  for  a  time  feed  in 

the    excavation    made    by    the  mother, 

but  soon  burrow  dow^nward  into  the  root, 

and  before  the  i^st  of  August,  the  majority 

of    them   have   l^ecome   full-grown,    and 

passed  into  the  pupal  stage.     By  Octoljcr 

nearly  all  have  become    fully  developed 

beetles,    but   they   make   no  attempt  to 

leave  the  plant  until  the  following  spring." 

The   spread    of   the   insect    occurs    very 

largely    in  the   spring  when  the  beetles 

fly  from  field  to  field,  seeking  uninfested 

plants  in  which  to  perpetuate  their  kind. 

It  has  been  observed  that  alsike  clover 
is  not  so  badly  injured  as  the  mammoth 
and  common  red  clover,  on  account  of 
the  fibrous  roots  and  the  tendency  of 
its  tap-root  to  divide.  In  Europe  alfalfa 
is  injured,  but  no  injury  has  yet  been 
reported  to  that  crop  in  this  country, 
though  it  may  be  anticipated. 

''  While  an  infested  clover  plant  sooner  or  later  succumbs  to 
an  attack  b}-  this  insect,  life  may  be  lengthened  or  shortened  by 
meteorological  conditions.  Thus,  if  the  spring  or  early  summer 
is  very  dry,  the  plants  begin  to  dry  in  patches  late  in  June,  as 
soon  as  the  hay  crop  is  removed;   but  if  there  is  much  rain  dur- 


FiG.  145.  —  Clover  root, 
showing  work  of  clover 
root  -  borer.  Slightly 
enlarged.  (After 
Webster,  U.  S.  D.  Agr.) 


202         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

ing  this  period,  the  weakened  plants  may  continue  to  live  until 
winter,  dying  out  before  spring.  In  either  case  the  farmer  is 
likely  to  be  misled  and  attribute  the  loss  to  the  weather."* 
Clover  is  practically  exempt  from  attack  the  first  year  as  the 
roots  are  not  large  enough  to  accommodate  the  insects,  and  it  is 
not  until  the  second  year  that  the  plants  are  destroyed. 

Control. — The  only  effective  moans  of  control  suggested  is 
summer  following  as  soon  as  the  hay  crop  has  been  removed. 
The  field  should  then  be  plowed  up  at  once,  before  the  larvae 
have  transformed  to  pupa?,  so  that  the  hot  sun,  and  dry  winds, 
will  dry  out  the  roots  of  the  clover  and  thus  starve  the  larva^, 
thereby  preventing  their  developing  and  migrating  to  other 
•fields.  Clover  fields  should  not  be  allowed  to  stand  over  two 
years  in  infested  localities.  No  injury  seems  to  be  done  in 
pastures.  A  system  of  rotation  in  which  the  crop  is  mowed  for  hay 
and  seed  the  first  year,  and  pastured  and  then  broken  up  the 
second  year,  should  keep  the  pest  under  control. 


The  Clover  Stem-borer  f 

Early  in  June  one  frequently  finds  the  beetles  of  the  Clover 

Stem-borer  here    and 


there  in  the  clover- 
field.  They  are  slen- 
tler,  shining  beetles, 
about  one-third  of  an 
inch  long,  with  a  red 
head  and  thorax  and 
l)Iuish-black  w  i  n  g  - 
covers.  The  beetles 
themselves  seem  to 
do  little  or  no  harm. 
Hibernating  over 
winter,  they  lay  eggs 


Fig.  146. — Clover  stem-borer  (Languria  mozardi): 
the  eggs  natural  size  and  magnified,  the 
beetle,  larva,  and  pupa — all  much  enlarged, 
and  above,  a  clover-stem  with  the  larva  at 
work  in  it.     (After  C'omstock.) 


*  Quotations   from  F.  M.  Webster,  The  Clover-root  Borer,  Circular  119, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr. 

f  Languria  mozardi  Fab.     Family  Erotylidce. 


INSECTS  INJURIOUS  TO  CLOVER  203 

in  the  pith  of  the  stems  early  in  June,  and  the  larva 
emerging  from  these  feed  upon  the  pith  of  the  stem,  often 
very  seriously  weakening  or  killing  it.  The  larvae  become  full- 
grown  in  a  short  time,  transform  to  pupce,  and  the  beetles  appear 
by  August. 

Clover-  is  only  one  of  a  dozen  food-plants  of  this  insect,  which 
is  widely  distributed.  It  rarely  does  any  considerable  injury 
where  clover  is  regularly  cut  in  early  summer  and  fall,  and  need 
not  be  feared  when  this  is  not  neglected. 

The  Clover  Leaf -weevil  * 

The  clover  leaf-weevil  is  a  stout,  oval  l)oetle,  about  one-third 
inch  long,  with  a  long,  thick  snout.  It  is  of  a  brownish  color, 
with  several  narrow  gray  lines  above  and  Ijroad  gray  stripes 
on  each  side,  and  with  twenty  rows  of  small,  deep  punctures 
on  the  wing-covers.  It  is  also  a  native  of  Europe  and  made  its 
first  appearance  in  the  same  section  of  western  New  York  as  the 
last  species,  about  1S<S1.  Since  then  it  has  spread  eastward  to 
Rhode  Island  and  ^'ermont,  southward  to  North  Carolina  and 
West  A^irginia,  and  westward  to  Wisconsin  and  Illinois.  Every 
few  j-ears  the  weevils  and  their  larvaj  destro}"  much  of  the  foliage 
in  restricted  localities,  but  rarely  are  they  very  injurious  the  next 
season.  Red  clover,  alfalfa,  and  white  clover  are  preferred  in  the 
order  named;  in  Illinois  the  mammoth  and  alsike  are  also   eaten. 

Life  History. — In  early  fall  the  female  beetles  lay  their  eggs 
in  crevices  among  the  stems  near  the  base  of  the  plant,  which 
hatch  in  from  three  to  six  weeks.  The  young  larvae  which  hatch 
from  them  are  without  legs,  but  manage  to  climb  by  means  of 
the  prominent  tubercles  on  the  lower  surface  of  the  body.  They 
are  light  yellowish-green,  becoming  deeper  green  as  they  grow 
older,  the  head  is  brown,  and  down  the  middle  of  the  back 
is  a  white  or  pale  yellow  stripe  bordered  with  reddish.  The 
larvae  become  partially  grown  before  winter  sets  in,  when  they 
hibernate  in  rubbish  or  just  under  the  soil  until  spring,  when 
they  continue  to  feed  upon  the  foliage  and  become  full-grown 
*  Phytonomus  punctatus  Fab.     Family  Curculionidce . 


204  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  May  and  early  June.  They  feed  mostly  at  night  and  are 
hardly  noticeable  in  the  day,  when  they  lie  protected  around 
the  base  of  the  plant,  lying  curled  up  head  to  tail.  The  injury 
to  the  foliage  is  quite  characteristic,  the  edges  of  the  leaves  being 
eaten  in  a  regular  manner  as  shown  in  Fig.  147.     When  full  grown 


Fig.  147. — Clover  leaf-weevil  (Phytonomus  punctatus  Fabr.) :  a,  egg  magnified 
and  natural  size;  bbbb,  larvae;  c,  recently  hatched  larva;  d,  head  of 
larva;  e,  jaws  of  the  same;  /,  cocoon;  g,  same  magnified  to  show  the 
meshes;  h,  pupa;  i,  weevil,  natural  size;  _/',  the  same  magnified;  k,  top 
view  of  the  beetle;  I,  tarsus  and  claws  of  the  beetle;  m,  antenna  of  the 
beetle.     (After  Riley.) 

the  larva  buries  itself  just  under  the  surface  of  the  soil  and  makes 
an  oval  cell,  in  which  it  spins  a  delicate  cocoon  consisting  of  a 
coarse  network  of  pale  yellow  threads,  which  later  turn  brown, 
as  shown  in  Fig.  147.  Occasionally  the  cocoon  is  made  on  the 
surface  or  among  the  bases  of  the  stems.  In  this  the  pupal 
stage  is  passed,  lasting  two  or  three  weeks;  the  beetles  being 
most   common   in  July   and   August.     The   damage   which   the 


INSECTS  INJURIOUS  TO   CLOVER  205 

beetles  do  to  the  second  crop  of  clover  is  fully  equal  that  done 
by  the  larvae  to  the  first,  and  is  more  apparent  because  the  soil 
is  then  dry  and  the  plant  grows  more  slowly. 

That  this  insect  has  not  become  a  more  serious  pest  is  due  to 
the  fact  that  as  often  as  it  becomes  excessively  abundant  the  larvae 
are  almost  completely  destroyed  by  a  fungous  disease,*  When 
affected  by  this  disease  the  larvae  climb  to  the  top  of  a  blade  of 
grass,  curl  tightly  around  the  tip,  and  soon  die,  first  becoming 
covered  with  a  white  mold  and  then  turning  to  a  jelly-like  mass. 
The  spores  of  the  fungus  become  scattered  to  healthy  individuals, 
which  soon  succumb,  so  that  before  long  nearly  all  are  destroyed, 
and  rarely  do  enough  survive  to  cause  trouble  the  next  year. 

Control. — On  account  of  this  disease  repeated  injury  has  been 
so  rare  that  no  means  of  artificial  control  has  been  necessary. 
"  The  necessity  for  the  employment  of  any  remedy  does  not 
appear  until  the  clover  is  well  on  in  its  second  year's  growth,"  says 
Dr.  Folsom  (I.e.).  "  If  damage  is  anticipated,  however,  it  would 
seem  advisable  to  pasture  the  clover  lightly  or  to  clip  back  in  the 
spring;  this  does  not  hurt  the  clover,  is  highly  desirable  as  a  means 
of  forestalling  the  attacks  of  some  other  clover  pests  (see  page 
214),  and  might  check  the  larvae  of  the  leaf-weevil  somewhat, 
though  it  is  possible  that  they  would  subsist  on  the  cut  Stems  until 
the  new  growth  started ;  and  in  cold  weather  they  can  live  a  long 
time  without  any  food.  After  the  second  season  red  clover  should 
1)e  plowed  under  to  get  rid  of  this  pest,  as  well  as  for  other  agricul- 
tural reasons." 

The  Alfalfa  Weevil  * 

In  recent  years  a  first  cousin  of  the  last  species  has  been  intro- 
duced into  Utah,  where  it  has  become  firmly  established  and 
promises  to  become  the  most  serious  obstacle  to  alfalfa  culture. 
The  alfalfa  weevil  is  a  native  of  Europe,  western  Asia,  and  north- 
ern Africa,  where  it  is  common  but  never  very  seriously  injurious. 

*  Empusa  spha- roper  ma  Fres. 

*  Phytonomus  murinus  Fab.  Family  Curculionidcr .  See  E.  G.  Titus, 
Bulletin  110,  Utah  Agr.  Exp.  Sta.,  and  F.  M.  Webster,  Circular  137,  Bureau 
of  Entomology,  U.  S.  Dept.  Agr. 


206     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


It  was  first  noticed  in  America  near  Salt  Lake  City,  Utah,  in  1904, 
and  has  been  increasing  and  spreading  until  it  now  occupies  an 
area  of  fully  100  scjuare  miles  around  Salt  Lake  City. 

The  beetles  are  from  one-eighth  to  three-sixteenth  inch  long, 
dark  brown,  marked  with  l)lack  and  gray  hairs  which  gives  them 
a  mottled  appearance  as  shown  in  Fig.  149e.     These  hairs  or  scales 

are  gradually  rubbed 
off,  so  that  in  spring 
many  individuals  are 
entirely  black  with 
small  grayish  spots. 

Life  History. — The 
beetles  seek  shelter  for 
hibernation  before 
frost  in  the  autumn, 
either  in  the  crowns 
of  the  alfalfa  plants, 
or  under  thick  grass, 
weeds,  rubbish,  leaves, 
or  in  hay  or  straw 
stacks.  Often  they 
winter  in  ]:)arns  where 
the  hay  is  stored,  the 
floors  of  which  are 
often  found  covered 
with  the  beetles  in 
winter  and  spring.  It  is  estimated  that  fully  80  per  cent  of  the 
weevils  survive  the  winter  in  Utah .  In  the  spring  the  beetles  emerge 
and  attack  the  young  alfalfa  plants  as  soon  as  there  is  sufficient  food 
for  them,  usually  late  in  March.  The  females  commence  laying 
eggs  in  early  April  and  continue  oviposition  until  early  July.  In 
early  spring  while  the  plants  are  small  the  females  often  push 
their  eggs  down  between  the  leaves,  but  the  usual  method  is  to 
insert  them  in  punctures  made  in  the  stem.  This  puncturing  of 
the  young  stems  often  results  in  considerable  damage  in  early 
spring.     A  single  alfalfa  plant  which  had  escaped  from  cultiva- 


FiG.  148. — The  alfalfa  weevil,  adults,  clustering 
on  and  attacking  sprig  of  alfalfa — natural  size. 
(After  Webster,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS   TO   CLOVER 


207 


tion  was  found  to  contain  127  of  these  punctures,  and  as  each 
puncture  contains  ten  or  fifteen  eggs,  this  phmt  probably  bore 
some  1200  eggs,  although  it  was  exceptional. 

The  eggs  hatch  in  about  ten  clays  and  the  small  white  larvae 
make  their  way  to  the  leaves,  in  which  they  cat  small  holes.  They 
soon  turn  a  decidedly  green  color,  and  when  full  grown  are  al^out 
one-half  inch  long  with  a  white  stripe  down  the  middle  of  the  back 
and  somewhat  curved  as  shown  in  Fig.  l-tOc.  They  attack  the 
young  leaves  and  crown  so  that  a  badly  infested  field  will  not  get 
over  six  inches  high;  too  short  to  mow.     The  larvae  arc  most 


Fig.  149. — The  alfalfa-weevil  {Phytonomus  inurinus):  a,  eggs;  b,  cocoon; 
c,  larva;  d,  pupa;  e,  adult — all  much  enlarged.  (After  Webster,  U.  S. 
Dept.  Agr.) 

abundant  in  May  and  decrease  through  June.  When  full  grown 
the  larvae  crawl  or  drop  to  the  ground  and  spin  their  cocoons 
in  the  dead  leaves  or  rubbish.  The  cocoon  is  globular  and 
composed  of  a  network  of  rather  coarse  white  threads,  Fig.  1496. 
In  it  the  larva  transforms  to  a  pupa,  which  stage  lasts  from 
one  to  two  weeks,  when  the  adult  beetle  emerges. 

From  early  to  midsummer  the  beetles  become  more  and  more 
abundant,  and  not  only  feed  on  the  fresh  growth,  but  attack  the 
bark  of  the  stems  so  that  where  excessively  alumdant  they  totally 
destroy  the  second  crop. 

"  The  entire  life  of  the  insect,  from  the  deposition  of  the  egg  to 
the  emergence  of  the  adult,  may  be  anywhere  from  forty  to  seventy 


208      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

clays,  while  the  beetle  itself  may  live,  including  the  winter,  from 
ten  to  fourteen  months." — Webster. 

Inasmuch  as  literally  millions  of  the  Ijeetles  have  been  gath- 
ered by  machines  from  a  single  acre,  and  as  the  beetles  have  been 
found  in  considera])le  numbers  on  freight  and  passenger  trains, 
it  is  highly  probable  that  the  pest  will  be  spread  by  the  several 
trunk-lines  of  railroad  which  pass  through  the  infested  region,  as 
in  many  places  alfalfa  has  escaped  from  fields  and  grows  as  a  weed 
along  the  railway  tracks.  It  is,  therefore,  highly  important  that 
alfalfa  growers  be  on  their  guard  against  this  pest  and  take  prompt 
measures  for  its  destruction  wherever  it  may  gain  a  foothold. 
The  weevils  also  spread  rapidly  by  flying  in  spring  and  summer, 
which  migration  is  aided  by  the  winds.  They  may  also  be  spread 
in  articles  shipped  from  an  infested  region  and  on  wagons  or  auto- 
mobiles. 

Control. — The  methods  of  control  have  not,  as  yet,  been  satis- 
factorily determined,  though  the  entomologist  of  the  Utah  Agri- 
cultural Experiment  Station,  E.  G.  Titus,  has  made  extensive 
experiments  with  various  methods,  from  whose  report  the  following 
summary  is  taken. 

Old  alfalfa  fields  are  always  worst  injured,  and  fields  should 
not  be  left  down  in  alfalfa  over  about  seven  years.  Thorough 
disking  in  the  early  spring  has  proved  to  be  one  of  the  essential 
factors  in  securing  a  good  crop,  as  it  increases  the  stand  and  stimu- 
lates a  quick  growth  which  enables  the  plants  to  better  withstand 
the  wee-^'^il  injury.  The  use  of  a  brush  drag  with  which  a  spike- 
tooth  harrow  is  combined  has  been  found  an  excellent  means  of 
killing  the  larvae,  as  they  are  knocked  to  the  ground  and  large 
numbers  killed  by  the  fine  dust.  If  the  field  is  very  hard  it  is 
advisable  to  disk  it  before  using  the  drag.  After  the  use  of  the  drag, 
the  fields  should  be  watered  where  there  is  irrigation.  Several 
machines  have  been  constructed  for  gathering  the  weevils  and 
have  proven  quite  satisfactory.  These  are  being  perfected  and 
promise  to  be  of  considerable  value  for  the  collection  of  the  weevils, 
particularly  when  used  in  conjunction  with  the  brush  drags.  In 
summarizing  the  methods  of  control,  Professor  Titus  recommends; 


INSECTS  INJURIOUS  TO  CLOVER 


209 


"  That  alfalfa  be  disked  in  early  spring  to  stimulate  it  to  better 
growth.  That  the  first  growth  be  cut  when  the  most  of  the  eggs 
have  been  laid  (middle  of  May)  and  then  brush-drag  the  field 
thoroughly.  Fields  should  l)e  ])rush-dragged  again  after  the  first 
crop  has  l)een  cut.  All  weeds  and  rubbish  should  be  cleaned 
from  the  fields,  yai'ds,  ditches  and  fence  rows  so  that  there  will  be 
less  opportunity  for  the  weevils  to  find  winter  shelter.  Alfalfa 
should  not  be  allowed  to  grow  more  than  seven  or  eight  years  in 
infested  districts." 


The  Clover-mite  * 

The  Clover-mite  is  nearly  related  to  the  common  red  spider 
of  greenhouses,  with  which  it  is  often  confused,  belonging  to  the 
same  family  of  vegetal^lc- 
feeding  mites.  It  is 
however,  about  twice  the 
size  of  the  red  spider,  being 
fully  three-tenths  of  an  inch 
long. 

Though  known  as  the 
clover-mite,  on  account  of 
its  feeding  upon  that  plant, 
yet  this  insect  w^as  first 
known  as,  and  is  still,  an 
important  enemy  of  fruit- 
trees,  more  especially  on 
the  Pacific  coast,  but  also  in 
other  sections  of  the  country . 
The  most  injury  seems  to 
have  been  done  to  clover  in 
the  Central  States  as  far 
south  as  Tennessee,  though  it  has  suffered  somewhat  even  in 
the  East. 

When  attacked  by  the   mite   the   leaves   of    clover   or  fruit- 

*  Bryobia  pratensia  Garman.     Family  T elranychida: .     See  C.  L.  Marlatt, 
Circular  19,  2d  Ser.,  Division  of  Entomology,  U.  S.  Dept.  Agr. 


Fig.    150. 


The    Clover-mite 
pratensis) . 


{Bryobia 


210      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

trees  become  yellow  and  have  a  sickly  appearance,  as  if  affected 
with  a  fungous  disease.  Especially  upon  the  upper  sides  of  the 
tender  leaves  of  clover  the  juices  arc  extracted  over  irregular 
areas,  looking  more  or  less  like  the  burrows  of  some  leaf -mining 
larvae.  Owing  to  the  small  size  of  the  mites  they  may  be  doing 
considerable  damage  to  the  foliage  and  yet  remain  unnoticed; 
but  in  the  egg  stage  the  pest  is  much  more  readily  detected  and 
attacked.  In  the  more  northern  States  the  eggs  are  laid  in  the 
fall,  and  do  not  hatch  until  the  next  spring.  Further  south, 
however,  the  adult  mites  hibernate  over  winter.  The  eggs  are 
of  a  reddish  color,  laid  upon  the  bark  of  trees,  especially  in  the 
crotches,  and  in  the  West  are  sometimes  so  thickly  placed  as  to 
cover  considerable  areas  two  or  three  layers  deep. 

When  the  adult  mites  leave  the  clover-fields  in  the  fall  to 
find  hibernating  quarters  upon  fruit-trees  for  the  winter,  they 
often  become  quite  a  nuisance  by  invading  dwelling-houses  which 
are  in  their  path.  This  is  more  particularly  the  case  throughout 
the  Mississippi  Valley. 

Remedies. — When  swarming  into  a  house  their  progress  may 
be  arrested  l)y  spraying  the  lower  part  of  the  building,  walls, 
etc.,  with  pure  kerosene  as  often  as  necessary.  Inside  the  house 
they  may  be  destroyed  ])y  the  use  of  pyrethrum  powder  (Persian 
insect-powder),  burning  brimstone,  or  spraying  with  benzine, 
care  being  taken  not  to  bring  the  latter  substance  near  the  fire. 

The  only  practical  wa}'  of  protecting  clover  from  the  mite 
.'s  by  destroying  the  eggs  and  hil^ernating  mites  upon  the  fruit- 
trees  in  winter.  This  may  be  done  by  burning  all  the  prunings 
and  thoroughly  spraying  the  trees  with  kerosene  emulsion  diluted 
with  five  parts  of  water,  or  with  miscible  oils  or  lime-sulfur 
mixture.  Such  a  spraying  will  also  protect  the  fruit-trees  from 
the  mite,  and  will  destroy  numerous  other  insects,  such  as  the 
pear-leaf  blister-mite,  which  hibernates  upon  the  trees.  Such 
small  insects,  so  minute  as  to  usually  escape  notice,  are  often 
responsible  for  a  poor  growth,  and  should  be  properly  checked 
whenever  known  to  be  injurious. 


INSECTS  INJURIOUS  TO  CLOVER 


211 


The  Pea-louse  * 

Although  this  aphid  is  worst  as  a  pest  of  peas  (see  page  322 
for  full  account)  it  passes  the  winter  on  red  and  crimson  clover 
which  occasionally  are  seriously  injuivd.  In  the  spring  of  1900, 
both  red  and  crimson  clover  were  badly  injured  in  Delaware, 
Maryland  and  Virginia,  while  in  DeKalb  County,  Illinois,  -con- 
siderable acreages  were  entirely  destroyed  in  August,  1903,  and 
more  or  less  injury  has  been  done  since  then.  Where  peas  are 
availal)lc  the  aphides  migrate  to  them  in  the  spring,  but  other- 


FiG.  151. — The  pea-aphis:    1,  winged  viviparous  female;    2,  wingless  vivip- 
arous female — greatly  enlarged.     (After  Folsom.) 


wise  they  continue  to  multiply  on  the  clover.  In  late  fall  they 
return  to  the  clover  upon  which  the  eggs  are  laid,  in  which  stage 
the  winter  is  passed,  though  in  open  winters  many  of  the  viviparous 
females  live  over  winter  on  the  clover. 

Control. — This  is  another  pest  which  is  usually  held  under 
control  by  a  fungous  disease,  and  as  the  fungus  does  not  develop 
in  dry  seasons,  with  dry  weather  the  ajjhis  increases  unchecked, 
while  with  a  normal  rainfall  it  is  usually  held  in  suljjection, 
Unfortunately  we  are  unable  to  predict  the  weather  probabilities, 
and  when  the  aphides  are  found  present  on  clover  in  considerable 
*  Macrosiphum  pisi  Kalt.     Family  Aphididce. 


212     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

numbers,  the  only  thing  to  tlo  is  to  cut  and  cure  it  as  soon  as  pos- 
sible, before  serious  damage  has  been  done.  The  drying  of  the 
clover  will  kill  most  of  the  aphides  or  cause  them  to  migrate. 
Spring  pasturing  or  clipping  might  result  in  destroying  a  sufficient 
number  of  the  aphides  so  that  no,  serious  damage  would  result 
later. 

The  Clover-seed  Midge  * 

The  Clover-seed  Midge  seems  to  occur  wherever  red  and  white 
clover  is  grown  in  this  country,  and  is  a  pest  which  must  be  taken 
into  consideration  in  raising  seed,  for  frequently  it  is  not  recognized 
as  the  cause  of  the  failure  of  the  seed  crop.  Alsike  clover,  and 
probably  mammoth  clover,  is  practically  uninjured,  as  it  flowers 
enough  later  to  escape  attack,  nor  is  alfalfa  infested. 

Life  History. — The  parent  of  all  this  troul)le  is  a  small  midge, 
one-twelfth  inch  long,  with  black  head  and  thorax  and 
reddish  abdomen,  so  small,  indeed,  that  it  will  rarely  be  noticed. 
The  antennae  have  sixteen  or  seventeen  segments,  and  the  wings 
have  but  few  veins,  as  shown  in  Fig.  152.  The  female  bears  a 
slender  retractile  ovipositor  which  when  extended  from  the  tip 
of  the  abdomen  is  fully  as  long  as  the  body,  while  the  tip  of  the 
abdomen  of  the  male  is  furnished  with  clasping  organs.  The 
midges  appear  in  late  spring  just  as  the  clover  commences  to 
head.  The  eggs  are  laid  among  the  hairy  spines  of  the  clover 
head  or  beneath  the  bracts  around  it,  are  yellowish  to  orange 
in  color,  of  an  oval  shape,  and  about  yio  ^^^^  long.  Upon 
hatching  the  maggot  works  its  way  into  the  open  end  of  a  floret, 
where  it  sucks  the  forming  seed,  and  prevents  the  petals  of  the 
floret  from  expanding,  so  that  although  some  of  the  flowers  in 
the  head  will  bloom,  the  field  as  a  whole  does  not  blossom  as 
usual.  The  maggot  is  footless,  white  to  orange-red  in  color, 
and  about  one-tenth  inch  long  when  full  grown.  Upon  becom- 
ing grown  in  late  June  and  the  first  week  of  July  the  maggots 
enter  the  soil  and  just  below  the  surface  make  tough,  oval,  silken 
cocoons,  in  which  they  pupate.  The  pupal  stage  lasts  about 
*  Dasyneura  leguminicola  Lintner.     Family  Cecidomyida;. 


INSECTS  INJURIOUS  TO   CLOVER 


213 


three  weeks  or  more,  and  the  flies  of  the  second  generation  appear 
in  Central  Illinois  in  late  July  and  early  August,  being  abundant 
as  the  second  crop  of  clover  heads  appear.  The  eggs  are  laid 
in  the  clover  heads  and  hatch  in  about  three  days,  and  the  second 
generation  of  maggots  do  the  worst  damage  to  the  seed  in  late 
August  and  early  September,  in  the  same  manner  as  did  the  first 
generation.     They  become  full  grown  by  frost     and    hibernate 


Fig.  152. — The  clover-flower  midge  {Dasyneura  leguminicola):  a,  enlarged 
side  view  of  female,  with  scales  denuded,  to  show  more  clearly  the  struc- 
ture; b,  head,  more  highly  magnified,  to  show  structure  of  the  eye, 
palpi,  and  basal  joints  of  antennae;  c,  tip  of  ovipositor,  highly  magnified 
and  showing  at  end  of  next  to  last  joint  the  manner  in  which  it  is  clothed 
with  minute  hairs;  d,  highly  magnified  antennal  joints,  their  minute  hairy 
clothing  shown  on  the  lower  one;  2,  o,  larva  enlarged,  ventral  view; 
b,  head  retracted,  highly  magnified.     (After  Riley.) 


either  as  full-grown  larvae,  in  which  case  they  pupate  early  the 
next  spring,  or  pupate  before  frost  and  pass  the  winter  as  pupae  in 
the  soil. 

Control. — Fortunately  this  pest  may  be  very  readih'  controlled 
by  adapting  the  methods  of  harvesting  so  as  to  destroy  the  devel- 
oping maggots.  If  clover  is  grown  alone  it  should  be  cut  early, 
before  the  maggots  have  become  mature.  This  results  in  drying 
up  the  food  plant  and  thus  destroying  the  larvae  and  hastens  the 
development  of  the  second  crop  of  clover  heads,  so  that  the  midges 


214      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

of  the  second  generation  have  but  few  green  heads  in  which  to  lay 
their  eggs.  Cutting  need  not  be  done  until  the  field  is  fairly  fresh 
with  bloom,  but  should  not  he  delayed  until  the  flowers  commence 
to  wither.  Where  timothy  and  clover  are  grown  together  they 
should  be  pastured  lightly  or  clipped  back  in  May,  which  will 
result  in  bringing  both  the  first  and  second  l^looming  after  the 
greatest  abundance  of  the  midges.  As  the  midges  do  not  travel 
far,  it  would  seem  advisable  to  ''  prevent  the  sporadic  heading  of 
first-year  clover  by  mowing  it  back  a  few  weeks  after  small  grains 
have  been  harvested,  at  a  time  when  growth  is  vigorous,  but  yet 
sufficiently  early  to  permit  considerable  growth  before  frost  sets  in. 
Volunteer  clover  should  always  be  cut,  as  it  affords  a  rich  nursery 
for  all  kinds  of  clover  insects." — Folsom. 


The  Clover-seed  Chalcid  * 

Evidence  accumulates  that  the  shortage  of  the   clover-seed 
crop  may  frequently  be  due  to  the  larva  of  a  little  chalcis-fly  which 

hollows  out  the  ripen- 
ing seed,  leaving  it 
brown,  brittle  and 
hollow,  so  that  the 
affected  hulls  are  ])lo  wn 
away  with  the  chaff  in 
threshing.  As  there  is 
no  evidence  of  the  pest 
in  the  appearance  of 
the  heads,  and  as  the 
worst  affected  seed  are 
thus  overlooked  in 
threshing,  its  work  will 
often  evade  detection. 


Fig.  153. — The  clover-seed  chalcis  {Bruchophagus 
funebris) :  adult  female,  much  enlarged ; 
antenna  of  male  at  left,  more  enlarged. 
(After  Webster,  U.  S.  Dept.  Agr.) 


If  the  seed  crop  is  short  it  will  ho  well  to  examine  seed  for  the 
larvte;  many  of  the  seed  will  be  found  shriveled  and  misshapen; 
and  frequently  consideral)lc  numbers  of  the  adults  will  issue  from 
the  seed  soon  after  threshing. 

*  BrucJtophagus  funebris  Howard.     Family  ChalcididcB. 


INSECTS  INJURIOUS  TO  CLOVER 


215 


The  adult  is  a  small  wasp-like  fly  one-twelfth  to  one-sixteenth 
inch  long,  black  in  color,  and  with  four  wings,  the  hind-wings  very 
small  and  the  fore-wings  with  but  a  single  vein.  It  belongs  to  a 
family  almost  all  of  which  are  parasitic  on  other  insects,  and  for 
many  years  it  was  thought  to  be  a  parasite  of  the  clover-seed 
midge,  until  its  true  role  was  discovered.  In  recent  years  exam- 
inations of  ripening  heads  from  all  parts  of  the  country  show  that 
it  is  probably  distributed  wherever  clover  is  grown  and  that  from 
20  to  80  per  cent  of  the  seed  is  often  destroyed.  Both  red  and 
crimson  clovers  are  attacked,  while  alfalfa  seed  is  not  so  badly 
injured. 


Fig.  154. — The  clover-seed  chalcis:  a,  egg — highly  magnified;  b,  larva 
and  head  more  enlarged;  c,  pupa — much  enlarged.  (After  Webster, 
U.  S.  Dept.  Agr.) 


Life  History. — The  winter  is  passed  by  the  fully  grown  larvse 
in  seed  on  the  ground.  The  adults  emerge  in  the  spring,  the  maxi- 
mum appearing  al^out  June  10th  in  central  Illinois,  according  to 
Dr.  Folsom,  to  whom  we  are  indebted  for  the  most  careful  stud}" 
of  the  pest.  The  females  deposit  their  eggs  in  the  soft  seed,  just 
as  the  floret  is  withering,  being  unal^le  to  penetrate  the  seed  after 
it  has  hardened.  The  egg  is  whitish,  about  y-J-^^  inch  long,  and 
with  a  peculiar  tail-like  appendage  (Fig.  154).  The  maggot-like 
larva  feeds  upon  the  seed,  gradualh'  hollowing  it  out,  and  M'hen  full 
grown  is  about  one-twelfth  inch  long,  stout  and  footless,  with  a 
small  head.  The  pupal  stage  is  passed  within  the  seed  and  a  sec- 
ond generation  of  adults  emerges  about  the  middle  of  August. 


216      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

These  lay  their  eggs  in  the  second  growth,  and  some  of  the  adults 
from  these  appear  the  same  season  and  the  rest  not  until  the  fol- 
lowing year.  There  seem  to  be  at  least  three  generations  a  year  in 
central  Illinois,  l)ut  the  life  history  is  complicated  by  the  irregu- 
larity in  the  time  of  development,  though  the  greatest  numbers  of 
adults  appear  about  June  10th  and  August  10th,  just  as  the  clover- 
seed  is  green. 

Control. — No  definite  experiments  have  been  made  in  the  con- 
trol of  this  pest,  but  from  the  knowledge  of  the  life  history  as 
given  above  there  seems  no  doubt  but  that  the  same  measures  as 
are  employed  against  the  clover-seed  midge  will  secure  immunity 
from  serious  injury. 

The  Clover-seed  Caterpillar  * 

"  In  its  ability  to  diminish  the  seed  crop,  this  pest  ranks  with 
the  seed-midge  and  the  seed-chalcid.  Attacking  a  clover  head 
that  is  green  or  partly  in  bloom,  the  little  caterpillar  eats  out  a 


Fig.  155. — Clover-seed  caterpillar  (Enarmonia  interstinctana) :  a,  caterpillar, 
b,  pupa;  c,  moth,  all  much  enlarged:  d,  moth  natural  size.  (After 
Osborn.) 


cavity  in  the  head,  destroying  many  of  the  unopened  buds  and 
some  of  the  tender  green  seeds,  and  spoiling  the  head  as  a  whole. 
When  no  young  clover  heads  are  at  hand,  the  caterpillar  feeds  on 

*  Enarmonia  interstinctana  Clem.     Family  Grapholithidce. 


INSECTS  INJURIOUS  TO  CLOVER  217 

tender  green  leaves  at  the  crown  of  the  plant." — Folsom.  Red 
clover  is  the  principal  food  plant,  but  white,  alsike,  and  probably 
mammoth  clovers  are  also  affected.  The  published  records  show 
that  it  occurs  in  the  northeastern  States  southwest  to  Missouri, 
but  it  doubtless  occurs  elsewhere  where  clover  is  grown,  as  it 
might  readily  be  carried  in  hay. 

Life  History. — The  adult  is  a  pretty  little  brown  moth,  with  a 
wing  expanse  of  two-fifths  inch,  with  silvery  markings  as  shown 
in  Fig.  155,  the  most  conspicuous  marks  forming  a  double  crescent 
when  the  wings  are  closed  ou  the  back.  The  moths  appear  about 
the  end  of  May  in  central  Illinois,  or  just  as  the  clover  is  coming 
into  bloom,  being  active  in  early  evening,  when  the  females  lay 
their  eggs  in  the  heads.  The  egg  is  circular  in  shape,  about  Yioo 
inch  in  diameter,  yellowish-white  in  color,  and  hatches  in  five  or 
six  days.  In  first-year  clover  that  has  not  headed  and  in  second- 
year  clover  recently  cut,  the  eggs  are  laid  on  young  stems  and  leaf- 
lets at  the  base  of  the  plant,  where  the  larvae  stay. 

"  Hatching  usually  at  the  base  of  a  green  clover-head;  the 
larva  eats  into  the  head,  destroying  the  green  florets  as  it  goes. 
A  small  green  head  is  often  destroyed  entirely,  before  it  is  many 
days  old;  a  larger  head  is  injured  only  locally  at  first,  remaining 
green  on  one 'side,  while  the  other  and  unaffected  side  may  come 
into  full  bloom."  Judging  from  the  appearance  of  the  head  the 
work  might  be  that  of  the  seed-midge,  but  whereas  it  is  hidden 
away  in  a  single  floret,  this  caterpillar  makes  a  large  dirty  excava- 
tion involving  many  florets,  and  is  readily  found  by  tearing  open 
the  head.  The  caterpillar  attacks  the  bases  of  the  florets,  includ- 
ing the  semifluid  ovules,  but  does  not  attack  seeds  which  have 
hardened.  "  Even  when  the  direct  injury  is  confined  to  a  portion 
of  the  clover-head,  the  entire  head  is  ruined,  for  it  at  length  dries 
up  and  loses  the  rest  of  the  florets,  leaving  only  the  dead  and  brown 
receptacle.  Less  conspicuous,  though  not  inconsiderable,  is  the 
injury  at  the  crown  of  the  plant,  done  chiefly  in  September  and 
October,  by  caterpillars  of  the  same  species  feeding  upon  the 
leaves." — Folsom.  The  total  injury  varies  greatly,  but  not  infre- 
quently 20  per  cent  of  the  heads  are  infested,  and  in  Iowa  infesta- 


218      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD  -^ 

tion  has  sometimes  been  exceedingly  severe.  In  any  event, 
every  head  destroyed  means  the  loss  of  more  than  one  hundred 
seeds. 

The  larvae  become  full  grown  in  four  to  five  weeks.  The  full 
grown  caterpillar  is  about  one-third  inch  long  a,nd  varies  in  color 
from  dirty-white  tinged  with  green  to  orange,  according  to  the 
food.  The  larva  spins  an  oval  white  silken  cocoon,  two-fifths 
inch  long,  either  in  the  head  or  at  the  surface  of  the  ground, 
which  is  more  or  less  covered  with  bits  of  excrement  and  floral  tis- 
sue. The  pupa  is  one-fifth  inch  long,  brown,  with  the  thorax  and 
wing-cases  darker,  and  with  two  transverse  rows  of  teeth  on  the 
back  of  the  abdominal  segments  except  the  last,  which  bears  six 
stout  blackish  hooks  at  the  tip.  The  pupal  stage  lasts  two  to 
three  weeks  and  a  second  generation  of  moths  emerges  about  the 
third  week  of  July  (in  central  Illinois) .  The  life  cycle  is  repeated 
in  the  same  manner  and  a  third  generation  of  moths  appears  about 
September  1st.  The  larvae  of  the  last  brood  feed  either  in  imma- 
ture clover-heads  or  at  the  crown  of  the  plant.  Most  of  them 
become  full  grown  and  transform  to  pupae,  in  which  stage  they 
hibernate  over  winter,  while  others  become  full  grown,  but  fail  to 
pupate  and  hibernate  under  rubbish. 

Control. — Cutting  and  storing  the  hay  crop  early  in  June  as 
advised  for  the  clover-seed  midge  will  kill  the  larvae  while  still 
in  the  heads.  ''  The  nay  should  be  handled  lightly  and  stacked 
or  stored  as  soon  as  possible.  OslDorn  and  Gossard  *  have  attested 
the  value  of  this  method,  and  have  given  these  further  recommenda- 
tions: (1)  Cut  volunteer  clover  in  early  June  and  dispose  of  the 
heads  speedily;  (2)  do  not  allow  clover  to  run  for  more  than  two 
years;  (3)  sow  seed  on  land  remote  from  old  fields;  (4)  pasture 
clover  in  the  fall  of  the  first  year;  (5)  plow  an  old  clover-field 
under  in  October  or  November  or  in  early  spring,  then  harrow 
and  roll.  These  practices  operate  at  the  same  time  against 
several  other  clover  pests." — Folsom. 

*  Osborn  and  Gossard,  Insect  Life,  Vol.  IV,  p.  254;  Bulletins  14  and  15, 
Iowa  Agr.  Exp.  Sta.;  22d  Report  Entomological  Society  of  Ontario,  p.  74. 
Gossard,  H.  A.,  Bulletin  19,  Iowa  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  CLOVER 


219 


The  Clover-hay  Worm  * 

The  clover-hay  worm  attacks  stacked  or  stored  clover,  par- 
ticularly where  it  is  held  over  a  year  or  where  placed  on  old  hay, 
eating  much  of  the  lower  layers  and  rendering  it  unfit  for  food. 


Fig.  156. — Clover-hay  worm,  greatly  enlarged.     (After  Folsom.) 

It  has  been  known  to  be  injurious  from  Kansas  eastward,  but 
occurs  throughout  most  of  North  America,  as  well  as  parts  of 
Europe,  Asia,  and  Africa. 


Fig.  157.^The  clover-hay  worm  moth,  wings  expanded  (after  Folsom)  and 
at  rest  (after  Pettit) — enlarged. 

"  The  larvic  attack  the  bottom  of  a  clover  stack  to  a  height 
of  2  feet  or  more  from  the  ground;  similarly,  in  the  barn,  they 
oc^ur  next  the  floor.  They  interweave  the  hay  with  white  silken 
webs,   intermixed   with   black   grains    of   excrement.  .   .   ;    they 


*  Hypsopygia  costalis  Fab.     Family  Pyrulididce. 


220     INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

reduce  much  of  the  hay  to  chaff,  and  their  webs  give  the  hay  the 
appearance  of  being  movildy;  in  fact,  such  hay  actually  becomes 
mouldy  if  it  has  Ijeen  lying  near  the  ground.  This  hay  is  refused 
by  horses  and  cattle  and  is  fit  only  to  be  burnt.  When  the  hay 
is  removed,  swarms  of  wriggling  brown  caterpillars  are  left." 
The  work  of  the.  caterpillars  is  usually  noticed  in  fate  winter  and 
spring. 

Life  History. — The  moths  appear  from  the  middle  of  June 
until  early  July  in  the  Northern  States  and  most  of  the  first 
generation  have  disappeared  by  the  end  of  July.  The  moths 
have  a  wing  expanse  just  under  an  inch,  with  silky  wings,  tinged 
with  purplish  above,  margined  with  orange  and  fringed  with 
golden  yellow.  On  each  side  of  the  fore-wings  are  two  largo, 
golden  spots  which  divide  the  anterior  margin  into  thirds  and 
continue  backward  as  narrow  lilac  lines  (Fig.  157).  The  hind- 
wings  are  marked  by  two  transverse,  wavy,  straw-colored  lines. 

As  soon  as  some  clover-hay  is  found  the  female  deposits  her 
eggs  and  the  caterpillars  feed  upon  it.  When  full  grown  they 
are  about  three-quarters  inch  long,  of  a  dull-brown  color.  The 
segments  are  divided  by  a  transverse  groove,  and  each  bears 
several  shining  areas,  with  a  fine  white  hair  in  each.  White 
silken  cocoons,  one-half  inch  long,  covered  with  bits  of  hay 
and  excrement,  are  made  by  the  larvae  in  the  hay  or  in  cracks 
and  crevices  of  the  barn,  in  which  they  transform  to  pupse,  which 
are  of  a  honey-yellow  color,  with  the  parts  clearly  defined  by  the 
darker  color  of  the  sutures.  The  moths  of  the  second  brood 
emerge  from  the  middle  of  August  until  September  1st,  but  may 
be  found  flying  until  late  October.  Caterpillars  of  all  sizes  may 
be  found  in  barns  throughout  the  winter  and  pupate  in  the  spring. 

Control. — Usually  no  serious  injury  is  done  except  where 
clover-hay  is  kept  over  the  second  year  or  longer.  When  it  is 
fed  out  each  spring,  before  the  next  crop  is  harvested,  there  is 
no  food  for  the  young  caterpillars,  and  they  perish  before  the 
new  crop  comes  in.  Consequently  mows  should  be  cleaned 
out  each  spring.  New  clover-hay  should  never  be  placed  on 
top  of  old  hay,  and  stacks  should  be  placed  at  some  little  distance 


INSECTS  INJURIOUS  TO  CLOVER  221 

from  the  old  stacks  if  possible.  Burn  up  the  refuse  from  old 
stacks,  or  what  remains  in  the  bottom  of  the  mow.  Stacks 
should  be  raised  above  the  ground  on  a  foundation  of  logs  or 
rails,  so  as  to  ke-ep  the  l^ottom  as  dry  and  cool  as  possible,  as  the 
caterpillars  love  warmth  and  moisture.  It  has  been  found  that 
salting  the  hay  for  2  or  3  feet  at  the  bottom  will  prevent  injury, 
and  many  farmers  salt  their  clover-hay,  using  about  two  quarts 
of  salt  to  the  ton. 


CHAPTER  XII 
INSECTS  INJURIOUS  TO  TOBACCO  * 


The  Tobacco  Flea-beetle  j 

The  Tobacco  Flea-beetle  is  one  of  the  imi^ortant  pests  of  that 
plant  throughout  the  Middle  States,  being  particularly  injurious 
to  young  plants.     The  beetles  damage  the  leaves  by  eating  small 


Fig.  158. — Tobacco  flea-beetle  {Epitrix  parvula):  a,  adult  beetle;  b,  larva, 
lateral  view;  c,  head  of  larva;  d,  posterior  leg  of  same;  e,  anal  segment, 
dorsal  view;  /,  pupa — a,  b,  f,  enlarged  about  fifteen  times;  c,  d,  c,  more 
enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

holes  in  the  upper  or  under  surfaces,  or  clear  through  them,  so 
that  when  badly  eaten  the  leaves  look  as  if  they  had  been  peppered 
with  shot.     The  little  beetles  which  do  this  damage  are  hardly 

*  See  L.  O.  Howard,  Farmers'  Bulletin  120,  U.  S.  Dept.  Agr.,  The  Prin- 
cipal Insects  Affecting  the  Tobacco  Plant.  A.  C.  Morgan,  Circular  123, 
Bureau  of  Entomology,  U.  S.^Dept.  Agr;  Yearbook,  U.  S.  Dept.  Agr.,  1910, 
pp.  281-296. 

t  Epitrix  parvula  Fab.     Family  Chrysomelidie. 

222 


INSECTS  INJURIOUS  TO  TOBACCO 


223 


more  than  one-twentieth  inch  long,  light  brown  in  color,  with 
a  dark  band  across  the  wing-covers.  A  few  of  them  could  do 
but  little  damage,  but  they  soon 
increase  in  rmmbers,  so  that  they 
swarm  over  the  leaves  and  injure 
them  badly.  Similar  injury  is  done 
to  potato,  egg-plant,  and  tomato, 
and  the  beetles  also  feed  on  horse- 
nettle,  nightshade^  and  Jamestown 
weed. 

Life  History. — The  eggs  are  laid 
in  the  soil  and  the  larva?  feed  upon 
the  roots  of  common  weeds,  such 
as  the  nightshade  and  Jamestown 
weed.  The  larva  is  delicate,  thread- 
like and  white,  except  the  yellow- 
ish head,  and  about  one-eighth 
inch  long.  It  pupates  in  the  soil. 
When  the  beetles  become  very  nu- 
merous the  larvae  sometimes  de- 
velop on  the  roots  of  tobacco,  but 
rarely  do  serious  damage.  The 
life  history  has  not  been  deter- 
mined exactly,  but  the  full  life 
cycle  seems  to  occupy  about  a 
month,  so  that  there  are  probably 
several  generations  in  a  year. 

Control. ^Ina,sm\ich.  as  the  larvae 
develop  on  the  roots  of  the  weeds 
mentioned,  it  is  evident  that  they 
should  be  kept  down  by  thorough 
cultivation.  Where  the  beetles  ap- 
pear, the  plants  should  ])e  sprayed 
or  dusted  with  Paris  green,  or 
probably  better,  arsenate  of  lead, 
the  same    as    for    the  horn-worm. 


Fig.  159. — T  o  b  a  c  c  o  leaves 
damaged  l)y  Epitrix  par- 
vula.  (After  Howard,  U. 
S.  Dept.  Agr.) 


Dipping  the  plants  in  arse- 


224         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

nate  of  lead,  1  pound  to  10  gallons  of  water,  just  as  they  are 
set,  has  been  found  to  afford  very  satisfactory  protection  in 
Connecticut. 

The  Tobacco  Stalk -worm  * 

Professor  W.  G.  Johnson  found  this  species,  also  knowai  as 
the  Corn-root  Webworm,  to  be  a  serious  pest  to  growing  tobacco- 
plants  in  southern  Maryland,  where  it  seems  to  have  been  a 
tobacco  pest  for  at  least  fifteen  years,  and  it  has  also  been  noted 
in  Delaware. 

The  Injury. — The  injury  to  tobacco  is  described  b}'  Professor 
Johnson  as  follows:  ^' The  uninjured  tobacco  had  a  leaf-spread 
of  from  ten  to  twelve  inches.  A  few  rods  ])eyond,  where  the  soil 
was  not  so  gravelly  and  better,  we  found  the  larva?  had  literally 
destroyed  the  first  and  second  plantings,  and  were  at  work  upon 
the  third,  damaging  it  severely,  although  the  ground  had  ])ceD. 
replanted  l^efore  the  last  planting.  Here  and  there  was  a  young 
plant  just  l>eginning  to  wilt,  and  invariably  we  found  the  larva  at 
work  either  in  the  stalk  or  at  the  base  of  the  plant  just  liclow  the 
surface  of  the  ground.  So  far  as  I  could  ascertain  the  attack  is 
always  at  the  surface  or  just  below.  In  many  instances  the 
larvae  had  hollowed  out  the  stalks  from  the  base  of  the  roots  to 
the  branches  of  the  first  leaves.  Many  plants  were  gnawed 
irregularly  around  the  stalk  below  the  surface,  and  some,  in  fact, 
were  completely  cut  off  at  the  surface,  the  insect  always  working 
from  below.  In  the  great  majority  of  cases  the  larvae  were  found 
in  a  small  mass  of  web  near  the  plant,  and  sometimes  within 
it.  In  one  plant,  less  than  six  inches  high,  we  found  four  larva? 
within  the  stalk,  but  as  a  rule  only  a  single  one  was   present." 

Professor  Johnson  concluded  "  (1)  that  it  is  most  likely  to 
occur  over  local  areas  in  tobacco  following  timothy  or  grass; 
(2)  that  the  character  of  the  soil  has  little  or  nothing  to  do 
with  its  ravages;  (3)  that  the  attack  upon  corn  is  also  a  frequent 
occurrence  in  the  same  section;  especially  when  following  grass 
or  timothy." 

*  Crambus  caliginosellua  Clem.  Family  Cramhida:.  See  p.  161  and 
Bull.  20,  n.  s.,  Div.  Eut.,  U.  S.  Dcpt.  Agr.,  pp.  99-101,  1899. 


INSECTS   INJURIOUS    TO   TOBACCO 


225 


Remedies. — He  recomnionded  "  (1)  that  growers  of  tobacco 
avoid  planting  upon  grass  or  timothy  sod;  (2)  that  where  grass 
land  is  plowed  down  it  would  be  well  to  put  it  in  wheat,  following 
with  clover,  before  tobacco.  If  desirable,  corn  could  follow 
the  grass  and  the  land  could  be  seeded  in  crimson  clover  at  the 
last  working.  This  would  serve  a  twofold  object  by  revealing 
the  exact  location  of  larvjB  in  the  area  under  cultivation  by  their 
attack  upon  corn,  when  they  could  be  destroyed  largely  by 
frequent  harrowing  and  rolling,  and  by  affording  a  most  excellent 
soil  crop  to  turn  down  the  following  spring,  which  would  be  a 
decided  advantage  to  the  tobacco;  that  if  it  is  found  necessary 
to  have  tobacco  following  grass,  it  should  be  l^roken  in  the  spring 
as  early  as  possible,  and  frequently  rolled  and  harrowed,  at  the 
same  time  delaying  the  setting  of  the  plants  as  long  as  possible 
in  order  to  destroy  and  starve  the  larvae  within  the  ground." 

The  Spined  Tobacco-bug  * 

Professor  H.  Garman  has  found  a  small  bug,  which  he  has 
termed  the  Spined  Tobacco-bug,  doing  more  or  less  injury  to  plants 


Fig.  160. — The  spined   tobacco-bug  {Euschistus  variolarius) ,  nymph  at  left; 
adult  at  right — enlarged,     (After  Howard,  U.  S.  Dept.  Agr.) 

in  Kentucky,  and  as  this  insect  is  widely  distributed  throughout  the 
country,  it  probably  does  more  or  less  damage  elsewhere,  though 
never  a  serious  pest.     Concerning  its  work,    he  says:     "  Occa- 

*  Euschistus  punctipes  Say  (variolarius  Pal.  Beauv.).     Family  Pentatom- 
idce.     See  Bulletin  No.  66,  Ky.  Agr.  Exp.  Sta.,  p.  33. 


226         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

sional  plants  in  tobacco-fields  are  at  times  observed  to  have  become 
suddenly  wilted,  the  leaves  hanging  limp,  much  as  if  the  stalk  had 
been  severed.  After  a  time  they  recover  again,  and,  beyond  a 
temporary  check  on  their  growth,  appear  to  have  suffered  but 
little  injury.  If  such  plants  are  searched  carefully  while  still 
wilted,  a  flat,  brown  bug  with  each  side  of  the  body  produced  into 
an  angle,  or  sharp  spine,  will  be  found  upon  the  stalk  along  the 
base  of  the  leaves.  It  is  very  shy  and  keeps  out  of  sight,  hence  any 
brisk  movement  on  the  injured  plants  is  likely  to  cause  it  to  drop  to 
the  ground  and  conceal  itself."  These  insects  are  true  bugs,  suck- 
ing their  food  through  a  beak,  which  is  bent  under  the  body 
between  the  legs  when  not  in  use.  They  are  about  half  an  inch  long, 
of  a  drab  color  above  and  greenish  or  yellowish  below.  Usually 
only  one  bug  is  found  on  a  plant,  so  that  the  best  way  to  prevent 
the  injury  is  to  pick  them  from  the  plants,  and  keep  down  such 
weeds  as  thistles  and  mulleins,  upon  which  such  insects  feed,  in 
the  adjoining  fields. 

The  Suck-fly  * 

One  of  the  worst  tobacco  pests  in  many  parts  of  Florida  is  a 
little  bug  called  by  the  planters  the  "  suck-fly,"  which  fortunately 
does  not  seem  to  have  become  a  pest  elsewhere.  They  insert  their 
little  beaks  into  the  tissue  of  the  leaf  and  suck  the  juices,  causing 
the  leaf  to  become  yellowish  and  wilted,  and  cracking  older  leaves 
so  that  they  become  ragged.  As  a  result  it  is  exceedingly  difficult, 
if  not  impossible,  to  properly  cure  l)adly  infested  leaves. 

Life  History. — The  adult  is  a  small  bug  about  one-eighth  inch 
long,  with  rather  long  yellowish-green  legs.  The  upper  surface  is 
black,  except  the  front  margin  and  a  central  stripe  of  yellow  on  the 
pro-thorax,  while  the  under  side  is  greenish.  The  "  flies  "  become 
numerous  enough  to  be  injurious  early  in  June,  usually  being 
noticed  first  in  one  corner  of  a  field  near  where  they  have  hiber- 
nated. They  rarely  do  serious  damage  to  the  first  crop,  but  the 
second  crop  and  late  tobacco  is  sometimes  entirely  destroyed. 
They  have  also  been  noted  in  the  Gulf  States  as  injuring  tomatoes. 

*  Dicyphus  minimus  Uhler.     Family  Capsida. 


INSECTS    INJURIOUS  TO   TOBACCO 


227 


The  eggs  are  deposited  singly  in  tlie  tissues  of  the  leaf  and  hatch 
in  about  four  days.  The  young  nymphs  feed  on  the  foliage,  as  do 
the  adults,  and  after  moulting  four  times  transform  to  adults  about 
eleven  days  later.     Thus  it  requires  but  about  a  fortnight  for  the 


Fig.  161. — The  suck-fly  (Dicyphus  minimus):  n,  newly  liatched;  b,  second 
stage;  c,  nymph;  d,  adult;  e,  head  and  beak  from  side— enlarged. 
(After  Howard,  U.  S.  Dept.  Agr.) 


development  of  a  brood,  so  that  the  pest  multiplies  very  rapidly 
and  in  a  few  weeks  becomes  so  numerous  that  hundreds  are  found 
on  a  single  leaf  and  serious  injury  is  inevitable. 

The  weather  plays  an  important  part  in  the  control  of  this 
pest,  as  many  of  the  insects  become  stuck  to  the  sticky  exudation 


228       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

given  off  by  the  glandular  hairs  of  the  tobacco,  and  if  there  be  fre- 
quent rains,  this  is  washed  off  and  the  insects  develop  unimpeded. 
The  bugs  arc  found  in  late  fall  until  frost,  but  the  exact  number  of 
generations  has  not  l)een  determined.  They  evidently  hibernate 
in  or  near  the  tobacco  field. 

Control. — Professor  A.  L.  Quaintance,  who  experimented  with 

remedies  in  Florida,  has  found,  curiously  enough,  that  the  best 

insecticide  against  this  pest  is  its  own  food,  tobacco.     A  solution 

of  concentrated  nicotine,  diluted  with  sixty  parts  of  water,  was 

found  very  effective  when  sprayed  upon  the  bugs.     It  should  be 

applied  with  a  bent-necked  nozzle  which  will  throw  a  fine  spray 

upon  both  surfaces  of  the  leaves,  as  most  of  the  young  are  on  the 

lower   surface.      Home-made  tobacco    decoction    (page  55)    was 

also  used,  but  did  not  prove  as  satisfactory.     The  spraying  should 

be  done  early  in  the  day,  when  the  adult  bugs  are  sluggish  and  do 

not   fly  readily.       Infested   areas    should  be   sprayed   when  the 

pest  first  makes  its  appearance  so  as  to   prevent  multiplication 

and  spread.     Thorough  cleaning  up  of  rubbish  and  destruction  of 

the  old  stalks  in  the  fall  will  be  of  service  against  this  as  well  as 

other  tobacco  pests.     A  few  plants  set  early  in  the  spring  would 

probably  attract  the  hibernating  bugs   as  they  emerge,  so  that 

they  might  l)e  readily  killed  upon  them. 

The  Hornworms  or  Tobacco-worms  * 

Of  all  the  insects  feeding  upon  tol)acco,  the  Hornworms  are 
the  most  widely  injurious  and  therefore  best  known.  The  cater- 
pillars of  two  species  of  moths  are  commonly  included  under  thig 
popuhir  name,  both  species  occurring  throughout  the  tobacco- 
growing  States,  the  northern  tobacco-worm  being  more  common 
in  the  North  and  the  southern  tobacco-worm  more  common  in  the 
South.  The  differences  in  the  adult  moths  may  be  readily  appre- 
ciated from  Figs.  162  and  163,  the  southern  form  being  darker  and 
with  brighter  orange  spots  on  the  abdomen,  and  the  white  lines  on 

*  Phlegethontius  quinquemaculata  Haworth  (Northern),  and  P.  sexia 
Johanssen  (Southern).     Family  Spfiingidce. 


INSECTS    INJURIOUS  TO  TOBACCO 


229 


the  hind-wings  being  less  distinct.  The  larva?  of  both  species 
commonly  attack  tomato  vines  and  arc  commonly  called  tomato 
worms  where  tobacco  is  not  grown. 

Life  History. — The  pupie  pass  tlu^  winter  several  inches  below 
the  surface  of  the  soil  and  from  them  the  moths  emerge  in  May  and 


Fig.  162. — Northern  tobacco-worm,  or  "  hornworm  "  (Phlegethontius  quinque- 
maculala):  c,  adult  moth;  6,  full-grown  larva;  c,  pupa — natural  size. 
(After  Howard,  U.  S.  Dept.  Agr.) 


June,  according  to  the  latitude  and  season.  The  females  deposit 
their  eggs  singly,  upon^  the  lower  surfaces  of  the  leaves,  from  which 
the  little  caterpillars  hatch  in  from  four  to  eight  days.  The  char- 
acteristic work  of  the  larvie  is  too  well  known  to  every  tobacco 
grower  to  necessitate  description.  The  caterpillars  become  full 
grown  in  about  three  weeks,  during  which  time  they  moult  some 
five  times.     The  full  grown  larva?  are  three  to  four  inches  long,  of 


230         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

a  dark  green  color  with  white  stripes  on  the  side  of  the  body,  those 
of  the  northern  species  having  a  V-shape,  while  those  of  the  south- 
ern species  being  simple  oblique  hands.  At  the  tip  of  the  al)domen 
is  a  stout  horn,  from  which  is  derived  the  name  of  hornworm, 
which  in  the  northern  species  is  black  and  in  the,  southern  is  red. 
The  pupae  are  formed  in  the  soil,  are  dark  brown,  about  two  inches 


Fig.  163. — Southern  tobacco-worm  {FhU'cjcthontius  sexia) :  a,  adult  moth; 
b,  full-grown  larva;  c,  pupa — natural  size.  (After  Howard,  U.  S.  Dept. 
Agr.) 


long,  and  have  a  peculiar  handle-like  process,  the  sheath  of  the 
proboscis,  which  somewhat  resembles  a  horn  and  which  may 
account  for  the  name  of  "  hornblowers,"  commonly  given  them  in 
Maryland  and  Virginia.  The  pupal  stage  lasts  about  three  weeks, 
when  the  adults  emerge,  the  whole  life;  cycle  requiring  from  six  to 
eight  weeks.  Usually  two  generations  occur  in  a  season  through- 
out most  of  the  tobacco  belt,  but  in  the  North  there  seems  to  be 


INSECTS   INJI'RIOUS  TO   TOBACCO 


231 


Fig.  164. — Hibernation  of  southern  tobacco- worm;  r,  pupa  in  hibernating 
cell  in  soil,  at  the  depth  of  which  pu])ation  usually  takes  place  in  the 
stiffer  soils;  a,  cross-section  of  pupal  cell  viewed  from  below;  6,  pupal 
cell  showing  entrance  hole  of  larva — two-third  natural  size.  (After 
A.  C.  Morgan,  U.  S.  Dept.  Agr.) 


232  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

but  one  generation,  and  in  the  Gulf  States  there  may  be  three 
generations.  Occasionally  the  worms  are  overlooked  in  cutting 
the  tobacco  and  are  carried  into  the  ])arn,  where  they  may  do 
considerable  injury  even  after  the  tolmcco  is  partially  dry. 

Control. — The  most  common  method  of  control  is  hand-pick- 
ing, usually  termed  "  worming."  In  seasons  when  the  worms  are 
not  overabundant  this  may  be  the  most  practical  method  of  con- 
trol, but  it  is  both  tiresome  and  expensive,  and  the  planter  has  no 
means  of  predicting  whether  the  worms  will  be  more  or  less  abun- 


FiG.  165. — Southern  tobacco- worm  killed  by  fungus.     (After  Garman.) 

dant.     Large  flocks  of  turkeys  driven  through  the  fields  will  aid 
most  efficiently  in  this  work. 

In  many  sections  the  worms  are  now  controlled  by  spraying 
or  dusting  with  Paris  green  or  arsenate  of  lead.  More  or  less  popu- 
lar prejudice  against  the  use  of  arsenicals  has  existed,  as  it  was 
thought  the  tobacco  might  be  poisonous  to  the  consumer.  Careful 
chemical  examinations  have  shown,  however,  that  the  amount 
left  on  the  foliage  after  three  sprayings  would  be  far  too  small  to 
have  any  deleterious  effect.  The  same  prejudice  formerly  existed 
against  the  use  of  arsenicals  on  potatoes,  cabbage  and  other  crops, 
but  experience  has  shown  it  to  be  unwarranted.  A  real  objection 
to  the  use  of  Paris  green  is  that  it  sometimes  slightly  burns  the 
foliage,  so  that  arsenate  of  lead  will  doubtless  be  found  preferable. 


INSECTS  INJURIOUS  TO  TOBACCO  233 

By  spraying  three  times,  the  worms  may  usually  be  entirely  con- 
tro  led  at  much  less  expense  than  by  hand-picking.  The  time  of 
the  spraying  will  depend  upon  the  latitude  and  season,  but  it 
should  be  applied  as  soon  as  each  brood  of  young  caterpillars 
appears.  Usually  one  spraying 
should  be  given  about  July  1st, 
a  second  early  in  August,  and 
another  in  about  two  weeks  to 
check  the  work  of  the  second 
brood,  which  is  the  most  inju- 
rious. One  pound  of  Paris  green  Fig.  166.— Southern  tobacco-worm 
to   160  gallons    of    water  is  suf-  ^;i^l^  cocoons  of  parasite.     (After 

ficient,  and    it   should  never  be 

used  stronger  than  1  pound  to  125  gallons.  Arsenate  of  lead  may 
be  used  at  the  rate  of  2  or  3  pounds  to  50  gallons  or  dusted  on  as 
a  powder.  These  treatments  will  also  aid  in  controlling  the  bud 
worms. 

A  method  of  killing  the  adult  moths  has  been  practiced  by 
many  planters  with  satisfactory  results.  It  consists  of  poisoning 
the  flowers  of  the  Jamestown  weed  (Datura  stramonium)  with  a 
sweetened  cobalt  solution.  The  flowers  are  placed  around  the 
fields  in  the  evening,  being  set  upright  in  holes  in  horizontal  slats, 
or  supported  by  sticks.  The  cobalt  solution  is  then  introduced 
into  them  by  means  of  a  quill,  or  dropper.  It  is  composed  of: 
cobalt,  1  ounce ;  molasses,  one-fourth  pint ;  and  water,  1  pint.  In 
their  search  for  flowers  the  moths  will  be  attracted  by  the  odor  of 
molasses  and  the  cobalt  of  the  solution  will  poison  them,  and  thus 
prevent  the  female  from  laying  some  200  eggs  toward  another 
brood  of  worms. 

As  the  pupse  hibernate  in  the  soil  it  is  evident  that  deep  plowing 
and  thorough  harrowing  in  late  fall  and  winter  of  land  which  has 
been  in  tobacco  will  result  in  destroying  many  of  them.  The 
destruction  of  the  stalks  and  cleaning  up  of  refuse  leaves  after  the 
crop  has  been  removed  is  also  of  importance,  as  the  larva?  may  con- 
tinue to  feed  in  the  field  and  become  full  grown  and  pupate 
where  by  the  destruction  of  their  food  this  might  be  prevented. 


234        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Natural  Enemies. — Very  frequently  worms  are  found  covered 
with  what  seem  to  be  small,  white  eggs.  These  are  not  eggs,  how- 
ever, but  are  the  small  silken  cocoons  of  a  little  wasp-like  parasite 
(Apanteles  congregatus)  whose  larvae  feed  internally  upon  the 
juices  of  the  worm  and  thus  ultimately  kill  it  before  it  transforms 
to  a  pupa.  Such  parasitized  worms  should  never  be  destroyed, 
as  the  parasites  are  of  more  value  than  the  damage  the  worm 
might  do.  Very  frequently  the  caterpillars  are  attacked  by  a  bac- 
terial disease  which  causes  them  to  turn  dark  and  become  shrunken 
and  flaccid. 

The  Budworms  * 

Two  caterpillars  of  the  same  genus  commonh'  attack  the  bud 
of  tobacco  and  have  been  distinguished  by  Dr.  L.  0.  Howard  as 
the  true  bud  worm  and  false  bud  worm,  the  latter  being  the  same 
as  the  well-known  cotton  ]>olhvorm  and  corn  ear-worm. 


Fig.  167. — The  true  budworm  {Chloriden  viresccns):  n,  adult  moth;  h,  full- 
grown  larva,  from  side;  c,  same,  from  above;  d,  seed-pod  l)ored  into  by 
larva;   e,  pupa — natural  size.     (After  Howard,  U.  S.  Dept.  Agr.) 


"  The  true  Ijudworm  {Chloridea  virescens)  occurs  in  the  more 
southern  portions  of  the  toljacco-growing  regions,"  says  Dr.  How- 
ard, t  "  but  has  not  been  noted  in  tobacco-fields  north  of  Maryland. 
The  adult  insect  is  a  small  greenish  moth,  well  illustrated  in 
Fig.  167.     The  larva  or  caterpillar  of  this  moth,  also  illustrated,  is 

*  Chloridea  virescens  Fab.,  and  Heliothis  obsolcta  Fab.     Family  A^ociM?(/fr. 
t  Farmers'  Bulletin  120,  U.  S.  Dept.  Agr.     The  Principal  Insects  Affecting 
the  Tobacco  Plant. 


INSECTS  INJURIOUS  TO  TOBACCO 


235 


nearly  alwa}'s  found  in  the  bud  of  the  tobacco-plant  about  the 
time  the  plant  is  ready  to  top.  In  some  seasons  they  occur  in 
large  numl)ers  and  damage  the  tobacco  considerably.  In  the 
eai-h'  part  of  the  season,  as  a  general  thing,  but  few  of  them  are 
found,  and  in  ordinary  seasons  they  are  not  especially  noticed 
during  the  early  "  worming  "  of  the  toljacco.  In  August  they 
begin  to  be  more  al)un- 
dant,  and  generally 
leave  the  plant  about 
the  end  of  the  month, 
entering  the  ground, 
transforming  to  pupto 
and  issuing  as  moths 
toward  the  end  of  Sep- 
tember. These  dates 
are  for  \"irginia,  but 
hold  reasonably  well 
as  far  south  as  Missis- 
sijDpi.  The  greatest 
damage  done  by  this 
insect  is  by  the  August 
brood,  when  it  enters 
the  rolled-up  leaves  or 
bud  of  the  plant.  In 
September  and  October 
the  next  generation  of 
caterpillars  is  found 
boring  into  the  seed- 
pod    and    occasionally 

into  the  flower-stem.  .  .  .  The  caterpillars  of  the  last  fall  genera- 
tion enter  the  ground  and  hibernate  as  pupa.  The  insect  has 
several  other  food-plants  aside  from  cotton,  but  its  most  abun- 
dant food  in  the  South  is  the  weed  known  as  ground  cherry 
(Physalis  viscosa)."  The  life  history  of  this  species  is  very 
similar,  therefore,  to  the  false  budworm  or  bollworm. 

The  corn  ear- worm  (see  page  181)  is  usually  found  attacking 


Fig.  168. — False  budworm  or  cotton  bollworm 
{Hcliothis  obsoleta):  o,  adult  moth;  b,  dark 
full-growTi  larva;  c,  light-colored  full-grown 
larva;  d,  pupa — natural  size,  (After  How- 
ard, U.  S.  Dept.  Agr.) 


236       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

tobacco  in  Virginia  and  Kentucky  only  late  in  the  season  after 
corn  has  commenced  to  harden.  It  then  bores  into  the  buds,  seed- 
pods,  and  flower-stalks,  in  the  same  manner  as  the  last  species.  In 
Florida,  however.  Professor  A.  L.  Quaintance  states  that  its  worst 
injury  is  done  early  in  the  season  before  corn  or  cotton  are  available, 
the  eggs  being  laid  in  the  bud  an  1  the  young  larvse  feeding  on  the 


Fig.  169. — Larva  of    false    budworm   {Heliothis  obsoleta),  showing  work  on 
seed-capsules  of  tobacco  plant.     (After  Quaintance.) 


unfolded  leaves,  doing  very  serious  injury.  In  Florida  the  corn 
ear-worm  or  false  budworm  is  more  common  than  the  former 
species. 

Control. — Poisoned  corn-meal  has  been  found  to  be  a  satisfac- 
tory remedy  for  both  species  when  they  bore  into  the  bud.  Mix  a 
half  teaspoonful  of  Paris  green  into  a  quart  of  finely  ground  corn- 
mea  and  sprinkle  into  the  buds  from  a  can  perforated  like  a  pepper 


INSECTS   INJtiRIOUS  TO  TOBACCO 


237 


can.  This  should  be  applietl  frequently,  especially  after  heavy 
rains.  Large  buds  should  be  opened  and  a  pinch  of  the  poison 
placed  within.  When  spraying  or  dusting  with  an  arsenical  is 
practiced  against  the  hornworms  it  will  aid  in  the  control  of  the 
budworms,  and  may  be  advisable  for  them  alone  where  injury  is 
serious.  Powdered  arsenate  of  lead  has  been  used  against  both 
these  insects  with  considerable  success  and  will  doubtless  obviate 
the  burning  which  has  been  experienced  when  using  Paris  green 
with  corn-meal.  When  the  injury  by  the  false  budworm  occurs 
only  late  in  the  season,  it  would  seem  that  the  moths  might  be 
attracted  to  a  trap  crop  of  late  corn  in  the  same  manner  as  cotton 
is  protected  from  it  (page  2") 7) . 

The  Tobacco  Leaf-miner  * 

The  larva  of  a  small  moth  has  become  quite  injurious  in  parts 
of  North  Carolina  and  Florida  by  mining  the  inside  of  the  leaf, 


Fig.  170. — Tobacco  leaf-miner  or  split-worm,  adult  moth  above;  larva  below 
at  right;  pupa  below  at  left,  with  side  view  of  enlarge  I  anal  segment — all 
enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 


and  is  thus  known  as  the  Tobacco  Leaf-miner.  This  insect  occurs 
in  other  parts  of  the  country,  but  has  become  injurious  only  in  the 
States  named  and  in  recent  years.     The  injury  is  done  by  the 


*  Phthorimfr  operculella  Zell.     Family  Tineidir. 


238        IN8ECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 


larvae  eating  out  irregular  patches  of  the  tissue  in  the  leaves,  leav- 
ing only  the  upper  and  lower  surfaces,  the  lower  leaves  being 
infested  the  worst.  The  leaves  are  ren- 
dered unfit  for  wrappers,  splitt  ng  and 
tearing  very  easily  on  account  of  these 
blotches.  A  larva  does  not  confine  its 
work  to  one  place,  but  makes  several 
mines,  and  a  single  larva  may  thus  destroy 
the  value  of  a  leaf  for  wrapping  purposes. 
This  migratory  habit  is  of  considerable 
importance,  as  in  leaving  the  old  and  in 
making  new  mines  the  larva?  must 
necessarily  eat  a  certain  amount  of  the 
surface  of  the  leaf,  and  can  thus  be  killed 
by  an  arsenical  spray.  The  life  history  of 
the  insect  is  not  completely  known,  but  as 
only  al)Out  twenty  days  are  rec^uired  for 
all  its  transformations,  several  Ijroods 
probably  occur  during  a  season.  The 
original  food-plant  of  this  pest  has  been 
found  to  1)e  the  common  horse-  or  bull- 
nettle  (Solanum  carolinense) ,  which  fact 
further  emphasizes  the  caution  already 
given,  to  keep  all  weeds  carefiilly  cut 
down  around  the  tobacco-field,  especially 
those  nearly  related  to  tobacco  botanically. 
Many  planters  destroy  the  larva?  by  simply 
crushing  them  w'th  the  hand,  and  this  can 
lie  done  quite  rapidly,  and  if  done  before 
the  mines  become  numerous  should  be 
sufficient  to  check  the  injury.  Where 
spraying  with  Paris  green  is  practised 
against  the  hornworm  it  should  be  sufficient  to  destroy  most  of 
the  miners,  as,  if  the  leaf  is  thoroughly  coated  with  poison,  they 
would  get  a  fatal  dose  in  starting  a  new  mine. 


Fig.  171.— Work  of 
split-worm  — reduced. 
(After  Howard,  U.  S. 
Dept.  Agr.) 


INSECTS    INJURIOUS  TO    TOBACCO 


239 


The  Cigarette-beetle  * 

The  most  serious  pest  of  dried  tobacco  is  the  Httle  brown 
Cigarette-beetle,  which  also  attacks  various  drugs  and  stored 
food  products.  The  beetle  is  but  one-sixteenth  inch  long,  of  a 
brownish  color,  'and  with  the  pro-thorax  bent  down  so  that  the 
head  is  oljscured  as  if  under  a  hood. 

"  Working  as  it  does  in  all  kinds  of  cured  tobacco  and  living 
in  this  substance  during  all  the  stages  of  its  existence,"  says 
Dr.  L.  O.  Howard,  "  it  damages  cigarettes  and  cigars  principally 
by  Ijoring  out  of  them,  making  round  holes  in  the  wrappers  so 
that  they  will  not  draw.     Leaf  tobacco  is  injured  for  wrapping 


CL  b  C 

Fig.  172. — The  cigarette-beetle:  a,  larva;  6,  pupa;  c,  adult;  d,  side  view  of 
adult;  e,  antenna — all  greatly  enlarged;  e,  still  more  enlarged.  (After 
Chittenden,  U.  S.  Dept.  Agr.) 

purposes  by  being  punctured  with  holes  made  both  by  the  larvae 
and  beetles,  and  fillers  and  finecut  are  injured  by  the  reduction 
of  their  substance  l^y  the  actual  amount  consumed  by  the  larvae." 
''  The  cigarette-beetle  is  practically  cosmopolitan,  and  probably 
occurs  in  most  tobacco  factories  in  the  Southern  States,  as  well 
as  in  most  wholesale  drug  stores.  In  the  far  South  this  insect 
multiplies  rapidly  throughout  the  greater  part  of  the  year,  and 
its  development  is  practically  continuous  in  artificially  warmed 
factories  farther  north." 

Life  HiMorii. — In  heated  factories  the  insect  may  ])e  found  in 
all  stages  thrcjughout  the  year.  Otherwise  it  seems  to  pass  the 
winter  months  in  the  larval  state.     The  larva  is  slightly  larger 

*  Lasioderma  serrkornc  Yah.     Family  Ftinidce. 


240        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

than  the  beetle  and  covered  with  hair  as  shown  in  Fig.  172.  When 
full  grown  it  spins  a  compact  silky  cocoon  covered  with  bits  of 
whatever  it  is  breeding  in  and  in  it  transforms  to  the  pupa.  In  a 
warm  room  the  entire  life  cycle  has  been  passed  in  forty-seven 
days,  and  it  seems  probable  that  in  the  District  of  Columbia, 
there  are  two  generations  a  year.  The  life  is  undoubtedly  inti- 
mately related  to  the  moisture  and  temperature  conditions  under 
which  it  lives. 

Control. — When  a  factory  or  storehouse  has  become  badly 
infested  a  thorough  cleaning  is  the  first  step  in  the  control  of 
the  pest,  as  tobacco  fragments  and  dust  are  usually  present  every- 
where and  ideal  conditions  for  the  multiplication  of  the  pest  are 
afforded. 

Infested  tobacco  should  be  opened  up,  if  packed  tightly, 
placed  in  tight  boxes  or  in  a  tight  room  and  exposed  to  the  fumes 
of  carbon  bisulfide,  using  it  the  same  as  for  grain  insects  (see  page 
57).  The  quantity  used  will  depend  upon  the  tightness  of  the 
enclosure,  the  way  in  which  the  tobacco  is  packed,  and  the  tem- 
perature. One  pound  to  every  200  cubic  feet  will  usually  be  ample. 
In  factories  where  the  beetle  is  abundant  the  tobacco  should  be 
steamed  before  use,  which  will  kill  all  stages  of  the  insect.  Loose 
tobacco,  cigars,  and  cigarettes,  should  not  be  left  exposed  to  the 
beetles,  but  should  be  covered  up  or  placed  in  tight  receptacles 
to  prevent  their  access.  Badly  infested  factories  and  storehouses 
may  be  fumigated  with  hydrocyanic  acid  gas  (see  page  57). 

Several  other  insects  are  more  or  less  serious  pests  of  tobacoo 
in  certain  parts  of  the  country  or  under- local  conditions.  The 
Tobacco  Thrips  *  has  caused  considerable  loss  to  growers  of 
wrapper  tobacco  in  Florida  where  it  is  grown  under  shade. 

*  Euthrips  nicotanixe  Hinds.  Order  Thysanoptera.  See  W.  A.  Hooker, 
Bulletin  65,  Circular  68.  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


CHAPTER    XIII 
,    INSECTS  INJURIOUS  TO  COTTON  * 

Plant-lice  f 

With  the  formation  of  the  first  true  leaves  of  cotton,  winged 
aphides  or  plant-lice  appear  in  large  numbers  on  the  under  side 
and  on  the  terminals,  the  "  buds  "  of  the  plants  often  being  black 
with  them.  Almost  all  of  them  are  the  common  greenish  Melon- 
aphis  I  (see  page  383),  which  infests  melons  later  in  the  season. 
It  is  evident,  therefore,  that  the  practice  of  planting  cotton 
between  rows  of  melons  is  undesirable.  The  aphides  migrate 
to  the  cotton  while  it  is  young  from  various  common  weeds  upon 
which  they  have  passed  the  winter. 

Another  species,  known  as  the  Bur-clover  Aphis  §  occurs  on 
cotton  at  about  the  same  time  and  is  not  readily  distinguishable 
from  the  previous  species,  but  is  darker  and  has  a  shining  reddish 
or  brownish-black  color. 

In  cold  weather  these  plant-lice  often  cause  considerable 
injury  to  the  young  plants,  and  greatly  retard  their  development, 
since  they  multiply  very  rapidly  and  feed  mostly  on  the  growing 
terminals.  If  there  be  a  few  warm  days,  however,  hordes  of 
small  hymenopterous  parasites  appear  and  in  a  few  days  often 
completely  rid  the  plants  of  the  pest. 

Control. — Although  these  aphides  may  be  destroyed  by  spray- 
ing with  kerosene  emulsion,  whale-oil  soap,    or  tobacco  water, 

*  See  Hunter  and  Hinds,  The  Mexican  Cotton  Boll  Weevil,  Bulletin  51, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Quaintance  and  Brues,  The  Cotton 
BoUworm,  Bulletin  50,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Sanderson, 
Miscellaneous  Cotton  Insects  of  Texas,  Bulletin  57,  Bureau  of  Entomology, 
Farmers'  Bulletin  223,  U.  S.  Dept.  Agr. 

t  Family  Aphididcp.  %  Aphis  gossypii  Glov. 

§  Aphis  medicaginis  Koch. 

—  241 


242  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  173. — The  cotton  worm  {AlubaDui  argillacea):  young  and  full-grown 
larvae  or  worms,  pupa,  cocoons  in  folded  leaves,  and  moths,  at  rest,  and 
with  wings  expanded — three-fourths  natural  size.     (After  Comstock.) 


INSECTS   INJURIOUS   TO  COTTON 


243 


yet  as  a  rule  their  use  on  any  considerable  scale  will  hardly  be 
profitable.  Keeping  the  fields  clear  of  weeds'  by  fall  and  winter 
plowing  will  untloubtedly  have  a  beneficial  effect  in  reducing 
the  numbers  of  aphides  and  in  most  cases  will  be  the  only  treat- 
ment necessar}'. 

The  Cotton  Worm  * 

Until  the  advent  of  the  boll  weevil,  the  cotton  worm  was 
much  the  most  serious  insect  pest  of  cotton.  Since  then,  however, 
its  importance  has  been  rather  overshadowed  in  the  mind  of  the 


Fig.  174. — Pimpla  conquisitor,  one  of  the  principal  parasites  of  the  cotton- 
caterpillar:  «,  larvae  enlarged;  h,  head  of  same  still  more  enlarged; 
c,  pupa;  d,  adult  female  enlarged;  e,  f,  end  of  abdomen  of  adult  male, 
still  more  enlarged.     (From  Fourth  Rept.  U.  S.  Entom.  Comm.) 

planter  by  the  onslaught  of  the  invading  Mexican  pest  and  where 
the  boll  weevil  is  abundant  the  stripping  of  the  late  foliage  b}' 
the  cotton  W'Orm  really  aids  in  the  control  of  the  weevil,  as  will 
be  explained  later. 

Life  History. — During  the  winter  months  the  adult  moth 
hibernates  in  the  most  southern  portion  of  the  cotton-belt,  in  the 
rank  wire-grass  occurring  in  the  more  thickly  timbered  regions. 
Only  a  few  of  these  survive,  but  they  are  very  capable  ancestors. 
In  early  March  they  lay  eggs  upon  volunteer  cotton  when  it  is 

*  Alabama  argillacea  Hubn.     Family  Noctuidce. 


244      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

only  an  inch  or  two  high.  The  eggs  are  hiid  singly,  usually  upon 
the  under  surface  of  the  leaves  near  the  top  of  the  plant,  and  about 
500  are  laid  by  each  female.  The  egg  is  of  a  flattened  convex 
shape,  bluish-greon  in  color,  and  with  prominent  ridges  converging 
to  the  apex.  In  midsummer  the  eggs  hatch  in  three  or  four  daj's, 
but  in  spring  and  autumn  a  much  longer  time  is  required.  The 
young  larvae  are  a  pale  yellow  color,  but  soon  assume  a  greenish 
tinge,  and  are  marked  with  dark  spots  which  become  more  dis- 
tinct after  the  first  moult,  when  they  become  marked  like  the  full- 


FiG.  175. — Cotton-worm  egg  parasite  (Pentarlhron  minulem):  a,  adult 
female,  greatly  enlarged;  b,  ovipositor;  c,  female  antenna;  d,  male 
anteima.     (From  Fourth  Rept.  U.  S.  Entom.  Comm.) 


grown  caterpillars,  being  more  or  less  striped  with  l:)lack.  During 
the  early  season  the  greenish  caterpillars  predominate,  but  later 
the  black  stripes  become  heavier  and  the  darker  forms  prevail. 
The  appetites  of  these  caterpillars  are  only  too  well  known  to 
the  cotton-grower.  At  first  they  are  content  with  eating  only 
the  under  surfaces  of  the  leaves,  occasionally  piercing  through. 
Then  the  leaves  commence  to  look  ragged,  and  when  they  become 
scarce  the  tender  twigs  and  buds  are  attacked.  When  they  are 
excessively  abundant  the  larvse  develop  cannabalistic  tendencies, 
like  the  boll  worms,  and  often  feed  upon  the  weaker  caterpillars. 


INSECTS  INJURIOUS  TO  COTTON  245 

The  larvsB  become  full  grown  in  from  one  to  three  weeks,  during 
which  time  they  moult  some  five  times. 

When  mature  the  caterpillar  crawls  into  a  folded  leaf,  which  is 
often  so  eaten  away  that  the  pupa  hangs  exposed,  and  there 
spins  around  it  a  thin  silken  cocoon  and  transforms  to  the  pupa, 
in  which  state  tl\e  insect  remains  dormant  for  from  one  to  four 
weeks,  when  it  emerges  as  an  adult  moth. 

The  moth  is  a  dull  olive-gray  color  with  a  wing  expanse  of 
about  1^  inches,  which  sometimes  have  a  purplish  lustre,  and  which 
are  marked  with  darker  lines  as  shown  in  Fig.  173.  Like  most  of 
the  owlet  moths  it  flies  only  after  sunset,  Init  unlike  them,  it  is 
not  confined  to  the  nectar  of  flowers  for  food,  as  its  mouth  is 
peculiarly  adapted  to  piercing  the  skin  of  ripe  fruit  and  feeding 
upon  its  juices.  The  moths  are  strong  fliers,  those  of  the  later 
broods  being  frequently  found  as  far  north  as  Canada. 

The  first  two  generations  develop  rapidly  and  in  the  extreme 
South  the  moths  emerge  by  early  April  and  are  carried  north- 
ward by  the  prevailing  winds.  Eggs  deposited  by  them  give 
rise  to  a  brood  of  moths  which  in  turn  fly  further  northward, 
and  thus  the  worms  are  gradually  found  throughout  the  whole 
cotton  b.elt,  though  with  a  considerable  confusion  between 
the  various  generations.  At  least  seven  generations  occur 
on  the  Gulf  Coast,  and  three  at  the  northern  limit  of  the 
species.  Considering  the  number  of  eggs  laid  b^  each  female 
and  this  number  of  generations,  it  may  be  readily  perceived  how 
such  immense  numbers  of  the  caterpillars  may  arise  by  the  latter 
part  of  the  season,  in  a  region  w^here  practically  none  remain 
over  winter.  If  none  was  killed,  the  progeny  of  a  single  moth 
after  four  generations  would  amount  to  over  300,000,000,000 
individuals,  or  if  placed  end  to  end,  the  third  generation  would 
be  enough  to  encircle  the  earth  at  the  equator  over  four  times. 

Enemies. — It  is  thus  very  fortunate  that  there  are  many 
deadly  enemies  of  the  cotton  worms,  which  commence  their  war- 
fare upon  them  with  their  first  appearance  in  spring  and  continue 
it  with  increasing  ardor  throughout  the  season.  One  of  the  most 
effective  of  these  is  a  minute  little  insect,  Trichogramma  pretiosa, 


246      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

which  develops  within  the  eggs.  Mr.  H.  G.  Hubbard  once 
observed  that  in  Florida  from  75  to  90  per  cent  of  the  fourth 
brood  of  eggs  were  destroyed  by  this  parasite,  while  only  three 
or  four  eggs  in  a  hundred  escaped  in  the  sixth  brood.  Another 
of  the  most  useful  parasites,  Pimpla  conquisitor,  was  noticed  as 
early  as  1847  to  destroy  nearly  all  of  the  pupae  of  the  last  brood. 
The  eggs  of  the  Piinpla  are  laid  upon  the  caterpillar,  and  the 
maggots  enter  the  w6rm  and  feed  upon  its  juices.  It  changes 
to  a  pupa  as  usual,  but  the  pupa  soon  dies,  and  large  numbers 
are  thus  killed.  Several  similar  parasites  prey  upon  the  cotton 
worm,  and  it  is  to  be  regretted  that  we  know  of  no  way  of  encourag- 
ing their  valuable  work.  The  common  insectivorous  birds  eat 
large  numbers  of  the  worms,  especially  when  they  are  scarce 
in  early  spring,  and  they  should  l^e  protected  by  enacting  and 
enforcing  most  stringent  laws  against  their  wanton  destruction' 

Control. — The  most  commonly  used  and  effective  remedy  is 
to  dust  the  plants  with  Paris  green.  Dusting  machines  drawn 
by  a  team  which  will  cover  four  rows  at  once  are  in  common  use. 
The  dust  may  be  applied  with  any  of  the  powder  guns,  but  it  is 
most  commonly  applied  to  two  rows  at  once  by  means  of  bags 
fastened  at  the  ends  of  a  i3olc  and  carried  by  a  man  on  Iwrseback, 
who  can  thus  dust  15  to  20  acres  per  day.  These  sacks  are  about 
10  inches  long  by  4  inches  in  diameter,  open  the  whole  length 
on  one  side  and  firmly  sewed  at  the  ends.  Eight-ounce  Osnaburg 
is  the  best  cloth  for  the  purpose.  A  strip  of  oak  or  strong  wood 
about  1^X2  inches,  and  5  feet  long,  has  a  1-inch  hole  bored 
through  it  5  inches  from  each  end,  and  to  this  the  sack  is  tacked, 
fastening  one  of  the  edges  of  the  opening  to  each  of  the  narrow 
sides  of  the  pole.  The  sacks  are  filled  through  the  holes  in  the  pole. 
When  freshly  filled  a  slight  jarring  will  shake  out  a  sufficient 
amount  of  the  poison,  but  when  nearly  empty  the  pole  should 
be  frequently  and  sharply  struck  with  a  short  stick  or  spaces 
will  be  missed.  The  poison  has  been  found  most  effective  with- 
out the  admixture  of  flour,  but  if  it  is  used,  lighter  cloth  should 
be  used  for  the  sacks. 

Besides  the  general  use  of  Paris  green  there  have  been  several 


INSECTS  INJURIOUS  TO  COTTON  247 

important  factors  which  have  aided  in  the  control  of  the  cotton 
worm,  so  that  it  is  by  no  means  as  much  of  an  enemy  of  the  cotton 
crop  as  formerly;  Among  the  most  important  of  these,  both 
from  an  entomological  and  general  agricultural  standpoint,  is 
the  diversification  and  rotation  of  crops,  now  coming  to  be  more 
and  more  practiced  by  the  progressive  agriculturists  of  the  South. 
This  alone  largely  prevents  the  rapid  spread  of  the  pest.  Since 
the  seed  has  become  such  a  valuable  product  of  cotton,  smaller 
varieties  with  many  seeds  and  a  short  fibre  are  being  grown, 
in  contrast  to  the  rank-growing,  long-fibre  sorts  formerly  pre- 
ferred. Thus  the  rows  are  more  open,  the  work  of  the  worms 
is  more  readily  detected  and  the  poison  more  easily  applied. 

Other  Caterpillars  Injuring  the  Foliage 

Several  of  our  common  caterpillars  which  ordinarily  feed  upon 
various  weeds  frequently  attack  cotton  foliage  in  restricted  local- 
ities and  do  more  or  less  serious  damage.  They  may  be  readily 
controlled  by  keeping  down  the  weeds  upon  which  they  normally 
feed  and  multiply  and  by  dusting  the  foliage  as  for  the  cotton 
worm  as  soon  as  thej'  are  noticed  upon  the  cotton  in  any  numbers. 

Among  the  more  common  of  these  leaf-eating  caterpillars 
is  the  Garden  Web  worm*  (see  page  406),  which  may  be  recognized 
by  the  fine  silken  web  which  it  spins  over  the  young  plants. 
Another  is  the  White-lined  Sphinx  Caterpillar,!  a  yellowish- 
green  caterpillar  with  black  eye-spots  and  faint  stripes,  varying 
to  blackish  with  j-ellow  spots,  and  distinguishable  from  most 
other  cotton  caterpillars  by  the  horn,  characteristic  of  sphingid 
caterpillars,  at  the  tip  of  the  abdomen.  The  Salt-marsh  Cater- 
pillar J  which  is  one  of  our  best-known  "  woolly  bear  "  cater- 
pillars, covered  with  black  and  red  hairs,  has  frequently  stripped 
cotton  of  foliage  in  Texas,  as  does  the  Fall  Army  Worm  (see  page 
lis),  when  it  becomes  locally  overabundant.  Many  other  species 
might  be  mentioned  which  do  more  or  less  loc^l  injury. 

*  Loxostege  similalis  Guen.     Family  Pyralidoe. 
t  Deilcphila  lineata  Fab.     Family  Sphingidce. 
X  Estigmene  acroea  Drury.     Family  Ardiidce. 


248      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Cotton  Square-borer  * 

Just  as  the  cotton  squares  commence  to  form  they  are  often 
bored  into  by  a  small  green  caterpillar  which  many  planters 
consider  a  stage  of  the  Ijollworm  and  which  others  have  called 
the  ''  sharpshooter."  This  injury  is  often  quite  serious  on  a 
small  area,  as  we  have  seen  10  per  cent  of  the  stalks  entirely 
denuded  of  squai'es  in  small  fields  in  Texas  where  this  insect  was 
abundant.  The  little  caterpillars  hollow  out  the  squares  in  the 
same  manner  as  does  the  Ijollworm,  often  destroying  all  of  those 
on  a  plant  knee-high  and  even  boring  into  the  tender  stalk.    The 


Fig.  176. — The  cotton  square-borer  (Urnnotes  melinus  Hbn.):  a,  aduh; 
b,  imderwing  of  same;  r,  larva;  d,  pupa — natural  size.  (After  Howard, 
U.  8.  Dept.  Agr.) 

caterpillars  are  l^right  green,  oval,  decidedly  flattened,  covered 
with  short  hairs  which  give  them  a  velvety  appearance,  and  with 
the  head  retracted  under  the  front  of  the  body,  thus  being  quite 
unlike  any  stage  of  the  bollworm.  They  are  the  larvse  of  a  dainty 
Uttle  butterfly  (Fig.  176),  of  a  bluish-black  color,  with  dark  red- 
dish lustre,  and  with  bright  retl  spots  on  the  posterior  border 
of  the  hind  wings,  common  around  cotton-fields.  The  small 
yellowish,  transparent  eggs  arc  laid  on  the  leaves  and  stems  of 
cotton,  cow-peas,  g&at-weed,  and  various  weeds,  and  the  larvae 
have  also  been  found  on  hops,  beans  and  cow-peas,  seeming  to 

*  Uranotes  melinus  Hbn.     Family  Lycaenidoe. 


INSECTS  INJURIOUS  TO  COTTON 


249 


prefer  the  latter  to  cotton.  The  eggs  hatch  in  from  two  to  five 
daj's,  the  larva?  become  grown  in  a  little  over  two  weeks,  and  the 
pupal  stage  averages  about  ten  days,  so  that  the  whole  life  cycle 
requires  about  a  month  in  Central  Texas,  where  there  are  three 
or  four  generations  in  a  season. 

Fortunately  for  the  planter  the  large  majorit}'  of  the  cater- 
pillars are  parasitized,  over  90  per  cent  of  the  June  generation 
having  been  thus  destroyed. 

Usually,  therefore,  it  is  hardly  worth  while  to  attempt  to  com- 
bat this  insect,  as  it  is  not  often  seriously  injurious  year  after 
year.  Should  remedial  treatment  be  necessary,  thorough  dust- 
ing with  Paris  green  or  arsenate  of  lead  would  probably  destroy 
most  of  them,  as  the  young  caterpillars,  like  the  bollworms, 
feed  to  some  extent  upon  the  foliage  l)efore  enteiing  the  squares. 

'*  Sharpshooters  "  * 

In  late  summer  reports  are  frequent  that  cotton  is  being 
injured  by  "  sharp- 
shooters," especially 
on  low  land.  These 
insects  are  reported  to 
puncture  the  squares 
and  bolls,  causing 
them  to  drop  prema- 
turely, a  small  black 
speck  showing  the 
spot  where  punctured. 
The  insect  which  has 
been  most  commonly 
credited  with  this 
work  is  the  Glassy- 
wingedSharpshooter,f 
but  with  it  are  usu- 
ally associated  several 
near     relatives     with 


*  Family  Jassidce. 


Fig.  177. — Tlie  glassy-winged  sharpshooter  {Ho- 
malodisca  triquetra  Fab.):  adult  at  left,  last 
stage  of  nymph  at  right,  young  nymph  below 
— all  enlarged.  (Author's  illustration,  U.  S. 
Dept.  Agr.) 

I  Ilomalodisca  triquetraF&h, 


250      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


similar  habits.*  Few  planters  are  able  to  identify  the  cause 
of  the  supposed  injury,  but  many  know  these  insects  as 
"  dodgers/'  from  their  habit  of  quickly  dodging  to  the  opposite 
side  of  the  stem  when  disturbed.  Extensive  observations  and 
repeated  experiments  during  two  seasons  failed  to  show  the 
slightest  evidence  that  these  insects  are  ever  injurious  to  cotton, 
though  they  are  common  upon  it,  the  supposed  injury  being 
undoubtedly  due  to  the  physiological  condition  of  the  plant  which 
causes  a  shedding  of  the  fruit  at  the  season  when  the  supposed 
injury  occurs. 


a  b  c 

Fig.    178. — ^Three     cotton    leaf  hoppers     commonly     called     sharpshooters: 
^  a,  Aulacizes  irrorata;  b,  Oncometopia  undala;'yc,  On'rometopia  lateralis — 
much  enlarged.     (Author's  illustration,  U.  S.  Dept.  Agr.) 

The  adult  insects  hibernate  in  rubl)ish  on  the  ground  near  the 
food-plants  and  appear  in  early  spring  on  the  elm,  hackberry,  red- 
bud,  Cottonwood,  willow,  and  the  tender  shoots  of  other  trees, 
especially  on  bottom-land  near  streams.  Here  they  suck  the 
juices  of  the  tender  leaves  and  deposit  their  eggs  in  them.  The 
eggs  are  laid  in  rows  of  ten  to  fifteen,  side  by  side,  just  under  the 
surface  of  the  leaf,  forming  a  blister-like  mark.     They  hatch  in  a 

*  Oncometopia  undata  Fab.,  0.  lateralis  Fab.,  and  Aulacizes  irrorata  Fab. 


INSECTS  INJURIOUS  TO  COTTON 


251 


few  days  and  the  j'oung  bugs,  or  nymphs,  are  grayish  or  yellowish 
in  color  and  resemble  the  adults  except  in  the  lack  of  wings.  Two 
or  three  generations  occur  annually  in  Texas,  and  the  insects  are 
not  common  on  cotton  until  midsummer.  They  are  exceedingly 
.fond  of  banana  trees,  sorghum  and  sunflowers,  sometimes  doing 
considerable  injury  to  the  latter,  but  there  is  no  evidence  for  con- 
sidering them  pests  of  cotton. 


The  Cotton  Leaf-bug  * 

This  insect  was  the  cause  of  considerable  damage  in  northern 


Fig.  179.— The  cotton  leaf -bug 
(Calocoris  rapidus) :  a,  adult ; 
b,  c,  d,  stages  in  growth  of 
nymph;  and  cotton  boll,  showing 
spots  injured  by  cotton  leaf-bug 
all  enlarged.  (Author's  illustra- 
tion, U.  S.  Dept.  Agr.) 


Texas  in  the  latter  part  of  the  season  of  1904,  and  had  been  pre- 
viously reported  as  a  pest  of  cotton,  though  its  injury  had  never 
t  Calocoris  rapidus  Say.     Family  Capsidce 


252         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

been  general.  It  punctures  the  squares  and  bolls,  either  causing 
them  to  drop  or  making  the  bolls  shrivel  or  decay  when  punctured. 
The  feeding  punctures  in  the  Ijolls  are  indicated  by  small  black 
spots,  resembling  diseased  places,  which  gradually  become  larger 
and  sunken,  evidently  due  to  some  poisonous  substance  intro- 
duced by  the  l)cak  of  the  insect  as  it  sucks  the  juices  of  the  boll. 
The  bugs  may  be  readily  recognized  from  Fig.  179,  and  by  the 
bright  red  spots  just  beyond  the  middle  of  the  wing.  The  young 
are  light  green  marked  with  red.  Several  generations  of  the  insect 
occur  annuall}-,  l)ut  its  life  history  and  habits  are  still  unknown, 
and  no  means  of  combating  it  Ixnni  devised. 


Other  Plant -bugs  * 

Several  other  species  of   plant-bugs   do    considerable   injury 
by   sucking  the    bolls   and    causing   them   to   shrink   or   decay. 


Fig.  180. — The  green  soldier-bug  {Nezara  hilaris):  a,  adult;  b,  beak;  c,  eggs. 
d,  end  of  egg  more  enlarged;  e,  young  nymph;  /,  last  stage  of  nymph. 
(After  Chittenden,  U.  S.  Dept.  Agr.) 

Among  these  are  the  so-called  "  pumpkin-bugs  "  or  ''  stink-bugs," 
of  which  a  large  green  species  f  is  the  most  commonly  injurious, 
while  the  blackish,  leaf-footed  plant-bugs,{  which  are  more  abun- 
dant on  cucurbs,  do  similar  injury. 


*See  A.  W.  Morrill,  Plant-bugs  Injurious  to  Cotton  Bolls. 
Bureau  of  Entomology,  IT.  S.  Dept.  Agr. 

t  Nezara  hilaris  Say.     Family  Pentatomidce. 
t  Lcptnglnssus  oppositus  Say.     Family  Coreido', 


Bulletin  86, 


INSECTS  INJURIOUS  TO  COTTON 


253 


"  Cotton-stainer  "  * 
The  cotton  stainer  or  rod-bug  is  stated  by  Hunter  to  be  the 
most  important  cotton  pest  in  Florida.  It  occurs  in  small  num- 
bers in  Georgia,  South  Carolina  and  Alabama,  but  do(»s  practically 
no  injury  there.  The  principal  damage  is  due  to  the  bugs  punctur- 
ing the  bolls  in  feeding  and  staining  the  lint  a  brownish  color. 
This  stain  seems  to  arise  from  the  injured  seed,  at  least  it  is  most 
noticeable    around   the    seed.     The    cocklebur   seems   to   be   the 


Fig.  ISl.     The   rod  bug   or   cottou-stiiincr   (^Lysdacus  suiureUus)   enlarged. 
a,  nymph;   b,  adult.     (From   "  Insect  Life.") 

most  important  of  the  native  food-plants,  though  the  bugs  feed 

on    the    night-shade    and    Hibiscus    and    rarely    attack  oranges. 

Prevention  of  the  growth  of  these  weeds  is  therefore  of  importance. 

As  the  bugs  usually  assemble  in  colonies,  their  red  color  may  be 

easily  observed  and  they  may  be  jarred  from  the  foliage  into 

buckets  containing  water  covered  with  a  film  of  kerosene.     In 

the  fall  and  winter  these  insects  assemble  in  numbers  on  piles 

of  cotton  seed,  which  may  thus  ht  used  as  traps  and  the  bugs 

killed  with  kerosene  or  hot  water. 

*  Dysdercus  suturellus  H.  Schf.    Family  Pyrrhocoridae.    See  W.  D.  Hunter, 
Circular  149,  Bureau  of  Entomology,  U.  S.  Department  of  Agriculture. 


254       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Cotton  Bollworm  * 

One  of  the  most  destructive  and  \videspread  pests  of  cotton  is 
the  bollworm,  the  same  insect  as  the  earworm  of  corn  already 
described  (page  ISl),  which  should  be  consulted  for  the  life  history 
and  description.  Throughout  the  cotton  Ijolt  the  moths  of  the 
third  generation  appear  about  August  1st.     At  that  time  the  ears 

of  corn  have  become  too 
hard  to  furnish  suitable 
food  for  the  larvae  and 
the  moths  therefore  lay 
their  eggs  on  the  cot- 
ton leaves,  though  if 
any  late  corn  is  in  silk 
it  is  decidedly  preferred. 
Thus  during  the  month 
of  August  the  cotton- is 
often  seriously  injured 
by  the  caterpillars  bor- 
ing into  the  bolls,  this 
injury  being  most  seri- 
ous in  recent  years  west 
of  the  Mississippi  and 
particularly  in  north 
Texas  and  Louisiana. 
The  total  damage  to  cot- 
ton is  estimated  at  upward  of  $20,000,000  per  annum.  Though 
more  or  less  damage  is  done  by  the  fourth  generation  of  worms, 
injury  is  rarely  serious,  as  the  numbei's  are  greatly  reduced 
by  parasites  and  unfavorable  weather  conditions. 

About  two-thirds  of  the  eggs  on  corn  are  parasitized  by 
a  tiny  little    insect   hardh'  visible    to    the    naked    eye,t    which 


Fig.  182. — Bollworm  at  work  on  cot  ton  bolls,  bor- 
ing into  grown  boll — slightly  reduced.  (After 
Quaiiitance  and  Brues,  U.  S.  Dept.  Agr.) 


*  Heliothis  ^obsoleta  Fab.  Family  Noctuidir.  See  Farmers'  Bulletin 
No.  290,  U.  S.  Dept.  Agr.,  by  F.  C.  Bishopp  and  C.  R.  Jones  and  Bulletin  50, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  by  A.  L.  Quaintance  and  C.  T. 
Brues. 

t  Tricliogramma  pretiosa  Riley. 


INSECTS    INJURIOUS  TO  COTl^ON  255 

becomes  so  abundant  late  in  the  season  as  to  effectively   check 
the  increase  of  the  pest. 

Wasps  are  effective  enemies  of  the  bollworms,  provisioning 
their  nests  with  them.  Several  species  of  tachina-flies  parasitize 
the  caterpillars,  while  not  a  few  are  killed  by  a  bacterial  disease. 
One  of  the  most  important  natural  factors  in  reducing  their  num- 
bers, however,  is  their  own  tendency  to  cannibalism,  the  larger 


Fig.    183. — Bollworm   boring  into   green   tomato.     (After   Quaintance   and 
Brues,  U.  S.  Dept.  Agr.) 

caterpillars  attacking  and  destroying  the  weaker  with  a  consequent 
marked  reduction  in  numbers. 

Control. — As  in  protecting'corn  from  this  pest,  the  most  effect- 
ive means  is  the  plowing  of  the  land  containing  the  pupa3  in  win- 
ter or  late  fall. 

Early  planting  of  early  fruiting  varieties  of  cotton,  with  a 
liberal  use  of  fertilizers,  and  frequent  cultivation,  so  as  to  hasten 
the  maturity  of  the  crop,  will  result  in  a  good  crop  being  made 
before  the  worst  injury  by  the  bollworm  occurs.  These  cultural 
measures  ensure  the  best  crops  even  where  there  are  no  insects 
to  be  avoided,  and  as  an  early  crop  is  less  injured  by  almost  all 
cotton  insects,  the  planter  should  adjust  his  methods  to  secure 
earliness. 


256      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


v^€?^ 


As  the  eggs  are  laid  mostly  on  the  cotton  leaves  and  the  little 
caterpillars  nibble  the  surface  before  boring  into  the  bolls,  the 
poisoning  of  the  foliage  when  the  eggs  are  hatching  will  result  in 

a  very  material  reduction  of  the 
subsequent  injury.  Paris  green  has 
been  most  generally  used,  but 
probably  powdered  arsenate  of  lead 
will  be  found  superior  to  it.  Paris 
green  has  been  used  at  the  rate 
of  3  pounds  per  acre,  applied  either 
pure  or  diluted  with  lime  or  flour, 
using  either  a  bag  and  pole,  hand  powder-gun  or  geared 
dusting  machine.  The  dusting  should  be  done  while  the  plants 
are  wet  with  dew.     When  not  followed  immediately  by  rain,  two 


Fig.  184. — Egg  of  boUworm ;  side 
and  top  views.  Highly  mag- 
nified. (From  Quaintance  and 
Brues,  U.  S.  Dept.  Agr.) 


Fig.  185. — BoUwomis  showing  variation  in  color,  upper  larva  green,  middle 
rose,  and  lower,  dark  browai — twice  natural  size.  (After  Quaintance  and 
Brues,  U.  S.  Dept.  Agr.) 


applications  should  be  sufficient,  the  first  when  the  eggs  commence 
to  hatch  in  numbers,  usually  between  July  25th  and  August  5th, 
and  the  second  about  a  week  later.  If  rains  follow,  the  applica- 
tions should  be  at  once  repeated. 


INSECTS  INJURIOUS  TO  COTTON 


257 


Inasmuch  as  the  moths  prefer  to  lay  their  eggs  on  corn-silk, 
cotton  may  be  very  effectively  protected  by  the  use  of  strips  of 
late  corn  and  cow-peas,  planted  through  the  cotton  so  as  to  act  as  a 
trap  crop.     Leave  vacant  strips  four  or  five  rods  wide  across  the 


Fig.  186. — Pupa  of  the  boUworm  in  its  Ijurrow  in  the  soil,  showing  burrow 
made  by  the  larva  and  filled  in,  and  the  exit  burrow  for  the  moth  also 
made  by  the  larva — natural  size.  (After  Quaintance  and  Brues,  U.  S. 
Dept.  Agr.) 


fields  when  planting  cotton.  About  June  1st  plant  these  with 
alternate  rows  of  Mexican  June  corn  and  cow-peas.  This  will  bring 
the  corn  into  silk  about  the  first  of  August  and  will  attract  the 


258         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


moths  to  lay  their  eggs  upon  it  instead  of  the  cotton,  while  the 
cow-peas  will  furnish  both  food  and  shelter  to  the  moths.  Corn 
should  never  be  planted  with  cotton  when  cotton  is  planted,  for 
instead  of  acting  as  a  trap  crop  it  merely  furnishes  food  upon 

which  the  worms 
multiply  during  the 
early  season  and 
forces  those  of  the 
third  generation  on 
the  cotton.  The 
strips  of  corn  and 
peas  should  be  cut 
as  soon  as  the  worms 
on  them  become 
fairly  grown  and 
the  land  plowed  to 
destroy  any  which  may  have  pupated.  "  On  large  plantations  the 
planting  of  small  areas  of  corn  here  and  there  in  the  fields  is  prac- 
ticable. Such  early  crops  as  potatoes,  oats,  or  wheat  may  be 
followed  by  corn  and  cow-peas  with  practically  the  same  results." 


Fig.  187. — The  moth  of  the  bollworm  or  com  ear- 
worm — enlarged  one-fourth.  (After  Quaintance 
and  Brues,  U.  S.  Dept.  Agr.) 


The  Cotton-boll  Cutworm  * 

The  larva  of  this  species  is  a  very  common  feeder  upon  the 
foliage  of  cotton  and  late  in  the  season  bores  into  the  bolls  in 
much  the  same  manner  as  the  bollworm.  Cotton  is  but  one 
of  a  long  list  of  food-plants,  however,  as  it  is  a  common  pest 
of  svigar-beets,  corn,  wheat,  cabbage,  potato,  asparagus,  salsify, 
peach,  raspberry,  violet,  cmcumber,  tomato,  turnips,  pea,  rape, 
pigweed,  cottonwood,  and  grasses  according  to  Chittenden. 
It  occurs  commonly  throughout  the  States  east  of  the  Rocky 
Mountains. 

The  moth  has  a  wing  expanse  of  about  1^  inches,  the  fore- 
wings  being  a  dark,  rich,  velvety  brown,  marked  with  black. 


*  Prodenia   ornithogalli   Guen.     Family   Noctuidce.     See   Sanderson,    I.e., 
and  F.  H.  Chittenden,  Bulletin  27,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  64. 


INSECTS  INJURIOUS  TO  COTTON  259 


Fig.  188. — ^Tip  of  ear  of  corn  showing  eggs  of  bollworm  or  com  ear-worm  on 
silks.     (After  Quaintance  and  Brues,  U,  S.  Dept.  Agr.) 


260 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


yellow  and  oclircous  as  shown  in  the  illustration,  while  the  hind- 
wings  are  a  light  gray.  The  grown  caterpillar  is  IJ  to  If  inches 
long,  and  is  quite  variable  in  coloration,  some  being  much  darker 
than  others,  as  shown  in  the  illustration.  The  three  whitish 
lines  and  the  double  row  of  triangular  brown  spots  along  the  back 
of  the  lighter  forms  will  easily  distinguish  this  caterpillar  from 
the  bollworm.* 

Life  History. — The  life  history  has  not  Ijcen  carefully  observed 


Fig.  ISO. — The  cotton-1)oll  cutworm  (Prodcnia  ornitliogulU  Guen.):  dark 
form  of  male  moth  above;  pale  form,  female  moth  below;  a,  pale  form 
of  larva;  h,  dark  form  of  larva;  c,  lateral  view  of  alxlominal  segments  of 
])ale  form;  d]  same  of  dark  form.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

in  the  North,  but  from  observations  mad(>  l)y  the  writer  in  Texas 
the  life  history  in  the  Gulf  States  seems  to  be  as  follows: 

The  winter  is  usuall}'  passed  in  the  pupal  stage  in  the  soil, 
though  possibly  a  few  moths,  emerging  late,  hibernate.  The 
first  brood  of  moths  appears  from  the  middle  of  May  until  the 
middle  of  June,  mostly  early  in  June.  A  second  l)rood  appears 
during  the  latter  half  of  July,  and  a  third  late  in  August  and  dur- 
ing September.  A  few  of  the  fourth  ]_)rood  may  emerge  in  Decem- 
ber, but  most  of  them  do  not  do  so  until  the  very  early  spring. 


*  See  Chittenden,  I.e.,  p.  30,  for  distinguishing  characters  of  related  species 
of  Prodenia. 


INSECTS  INJURIOUS  TO  COTTON  261 

when  they  lay  eggs  upon  various  weeds  on  which  the  larvae  feed 
until  cotton  appears.  The  length  of  time  occupied  in  the  dif- 
ferent stages  is  seen  to  be  quite  variable,  but  is  approximately 
six  days  for  the  egg,  twenty  days  for  the  larva,  and  thirteen  days 
(usually  ten  to  fifteen  days)  for  the  pupa — making  a  total  of 
about  forty  days  for  the  complete  life  cycle.  Dr.  Chittenden 
believes  that  there  are  two  generations  in  the  North  and  probably 
three  in  the  latitude  of  the  District  of  Columbia. 

Control. — This  species  has  not  been  sufficiently  injurious  on 
cotton  to  warrant  extensive  experiments  in  its  control.  Where 
it  attacks  young  plants  of  cotton  or  other  crops,  it  may  Ijc  com- 
bated with  the  means  suggested  for  other  cutworms  on  page  85. 
Where  it  becomes  injurious  to  the  bolls,  it  might  be  controlled 
by  thorough  dusting  or  spraying  with  arsenicals,  which  would 
destroy  the  young  larva?  while  they  are  still  feeding  on  the  foliage. 

The  Mexican  Cotton  Boll  Weevil  * 

Not  since  the  invasion  of  the  Mississippi  Valley  by  the  Rocky 
Mountain  locusts  in  the  70's  has  any  insect  caused  such  ruin 
to  any  staple  crop  as  has  the  boll  weevil  in  the  territory  affected 
during  the  past  ten  years,  and  it  is  one  of  the  factors  in  the  recent 
high  prices  of  cotton. 

Like  several  of  the  worst  insect  pests  of  the  South  it  is  a  native 
of  Central  America  and  came  to  us  from  Mexico,  crossing  the 
Rio  Grande  at  Brownsville,  Texas,  about  1S90.  As  early  as  1862 
the  weevil  caused  the  growers  at  Monclova,  Mexico,  to  abandon 
cotton  culture  and  when  they  again  planted  it  in  1893,  the  beetle 
promptly  appeared  and  destroyed  the  entire  crop.  It  multiplied 
rapidly  in  south  Texas,  ruining  the  crops,  and  by  1895  had  spread 
northward  to  a  line  extending  eastward  from  San  Antonio. 
Since  then  it  has  spread  northward  and  eastward,  about  sixty 
miles  a  year,  until  in  1905  it  had  covered  all  of  Texas  and  western 
Louisiana  and  is  now  founfl  throughout  the  cotton  area  of  those 

*  Anthcrwrnus  grandis  Boh.  Family  Curculionidcc .  See  W.  D.  Hunter, 
"The  Boll  Weevil  Problem,"  Farmers'  Bulletin  344,  U.  S.  Dept.  Agr. ;  and 
Hunter  and  Hinds,  Bulletin  51,  Bureau  of  Entomlcgy,  U.  8.  Dept.  Agr. 


262        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

States  and  in  Mississippi,  Arkansas,  Oklahoma,  and  South- 
western Alabama.  There  seems  to  be  no  reason  why  it  should 
not  continue  to  spread  throughout  the  cotton  belt. 


mmi^'^'^ 


Fig.  190. — The  cotton  boll  weevil,  natural  size,  showing  variation  in 
size  and  color. 

In  1904,  after  an  exhaustive  study  of  all  available  data,  the 
writer  estimated  the  loss  in  Texas  alone  at  .$25,000,000,  and 

that  the  pest  had  then  cost  the 
State  $100,000,000.  Owing  to 
decrease  in  acreage  and  the  gen- 
eral use  of  methods  for  preventing 
or  a^'oiding  injury,  the  injury 
has  not  increased  proportion- 
ately to  the  spread  of  the  pest, 
but  the  total  annual  loss  is  at 
least  as  much  as  in  1904,  though 
no  accurate  estimates  have  been 
recently  made  for  the  whole  ter- 
ritory affected. 

Life  History. — The  parent  of 
all  this  damage  is  a  small  brownish  beetle  about  one-quarter  inch 
long,  varying  from  one-eighth  to  one-third,  including  the  snout, 
which  is  about  half  as  long  as  the  body.  Recently  emerged 
weevils  are  light  yellowish  in  color,  but  they  soon  become  grayish- 
brown  and  later  almost  blackish.  There  are  many  nearly  related 
weevils  which  very  closely  resemble  the  boll  weevil,  and  only  an 
entomologist  can  identify  the  species  with  certainty,  but  the  two 
teeth   at  the  tip  of  the  femora  of  the  fore-legs  (Fig.  191),  are  the 


Fig.  191. — ^The  cotton  boll  weevil — 
enlari^ed. 


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264        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

most  characteristic  structure  by  which  it  may  be  distinguished. 
The  boll  weevil  feeds  only  upon  cotton,  and  weevils  found  feeding 
on  other  plants  are  certainly  of  other  species. 


Fig.  193. — Cotton  square  with  liracts  opened  to  show  weevil  at  work  on  the 
bud,  which  shows  a  feeding  puncture. 


Fig.  194.— The  cotton  boll  weevil;  eggs  among  the  anthers  at  points  indi- 
cated by  arrows,  the  cross-section  at  the  right  showing  opening  through 
which  egg  was  deposited — greatly  enlarged. 

The  weevils  commence  to  emerge  from  hibernation  soon  after 
cotton  is  up  and  continue  to  emerge  until  the  cotton  commences 
to  square  freely.    During  the  spring  the  beetles  feed  on  the  foliage, 


INSECTS  INJURIOUS  TO  COTTON  265 

particularly  in  the  tender  terminals,  and  as  soon  as  squares  are 
formed  the  females  commence  to  lay  their  eggs  in  them.  Each 
female  lays  an  average  of  about  140  eggs,  laying  four  or  five  a  day. 
The  female  drills  a  small  cavity  in  the  S(|uare  and  in  it  deposits 
a  small  oval  white  egg,  which  hatches  in  about  three  days. 
The  grub  feeds  upon  the  embryo  flower,  which  usually  fails 
to  develop,  and  the  infested  square  generally  falls  to  the  ground. 
In  from  seven  to  twelve  days  the  larva  is  full  grown  and  changes 
to  the  pupa,  which  stage  lasts  from  three  to  five  days.     Thus 


Fig.  195. — The  cotton  boll  weevil,  larva  and  pupa — enlarged. 

from  egg  to  adult  requires  from  two  to  three  weeks,  though 
climatic  conditions  cause  considerable  variation  in  the  length 
of  time.  The  larva  is  a  footless,  white  grul3,  with  brown  head, 
which  lies  curled  up  in  the  square  as  shown  in  Fig.  195,  where 
the  soft  white  pupa  is  also  found.  The  adult  weevils  feed  entirely 
during  the  day.  Their  length  of  life  depends  upon  various 
conditions,  but  in  the  summer  season  the  majority  do  not  live 
over  sixty  days,  while  during  the  cooler  part  of  the  year  those 
which  hibernate  live  five  or  six  months.  Many  squares  are 
destroyed  by  the  feeding  punctures  of  the  weevils.  "  The  males 
feed  upon  the  squares  and  bolls  without  moving  until  the  food 
begins  to  deteriorate.  The  females  refrain  from  depositing  in 
squares  visited  by  other  femal(\s.  This  applies  throughout 
most  of  the  season,  but  late  in  the  fall,  when  all  the  fruit  has 
become  infested,  several  eggs  may  be  placed  in  a  single  square 


266       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

or  boll.  As  many  as  fifteen  larvse  have  been  found  in  a  boll. 
The  squares  are  greatly  preferred  as  food  and  as  places  for  deposit- 
ing eggs.  As  long  as  a  supply  of  squares  is  present  the  bolls  are 
not  damaged  to  any  serious  extent.  The  bolls,  therefore,  have 
a  fair  chance  to  develop  as  long  as  squares  are  being  formed. 
Whenever  frost  or  other  unfavorable  weather  causes  the  plants 
to   cease  putting  on  squares,   the  weevils   attack  the  bolls.     A 


Fig.  196. — Cotton  squares  broken  open,  showing  the  boll  weevil  larvje  within 

— enlarged. 

conservative  estimate  of  the  possible  progeny  of  a  single  pair 
of  weevils  during  a  season  beginning  on  June  20,  and  extending 
to  November  4,  is  12,755,100." — Hunter.  Although  the  weevil 
may  develop  from  egg  to  adult  in  two  or  three  weeks,  it  requires 
an  average  of  about  forty-three  days  for  a  complete  generation, 
and  there  arc  probal:)ly  not  over  four  or  five  generations  in  a 
season. 

With   the   first   killing  frosts,   most   of  the  immature  stages 
developing  are  killed,  though  in  south  Texas  they  often  develop 


INSECTS  INJURIOUS  TO  COTTON 


267 


during  the  winter,  and  the  adult  weevils  soon  go  into  hibernation. 
When  seeking  places  for  hibernation  the  weevils  migrate  from 
field  to  field,  and  it  is  at  this  season  that  the  principal  migration 
of  the  pest  takes  place.  The  weevils  may  hibernate  in  hedges, 
woods,  corn-fields,  haystacks,  or  farm  Ijuildings,  particularly 
about  seed-houses  or  similar  situations.  Experiments  have 
shown  that  Spanish  moss  forms  an  exceedingly  favorable  place 
for  hibernation,  and  that  many  weevils  pass  the  winter  in  it  on 
trees  some  distance  above  the  ground.  Others  may  hiber- 
nate in  the  cotton-field,  crawling  into  cracks,  under  grass, 
weeds,  and  trash,  and  into  the 
empty  cotton  burrs,  while  in 
the  more  southern  sections 
many  hibernate  in  injured 
bolls.  The  weevils  w  h  i  c  h 
hibernate  most  successfully 
do  so  outside  of  the  cotton - 
fields.  The  number  which 
survive  the  winter  has  been 
accurately  determined  under 
various  conditions  for  several 
seasons,  and  depends  upon 
the  minimum  temperature, 
the  amount  of  moisture,  and 
the  kind  of  shelter.  Thus  in 
central  Texas  but  2  or  3  per 

cent  survive  in  many  normal  winters,  while  in  the  open  winter  of 
1906-07  11.5  per  cent  survived;  in  south  Texas  15  per  cent  may 
survive,  and  in  experiments  made  in  Central  Louisiana  in  1908- 
09  with  rather  favorable  conditions  20  per  cent  survived.  The 
importance  of  reducing  the  number  whicn  survive  the  winter  is 
evident. 

Natural  Control. — If  infested  squares  fall  to  the  ground  and  lie 
on  the  unshaded,  hot  soil  the  larvse  or  pupae  within  them  are  soon 
killed.  As  many  as  40  per  cent  of  the  immature  stages  have  thus 
been  found  dead  in  many  fields.     The  importance  of  wide  rows 


Jig.  197. — Cotton  boll  weevils  hiber- 
nating in  locks  of  cotton  removed 
from  old  bolls  left  on  stalks  over 
winter. 


268      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  varieties  which  produce  little  shade  is  therefore  apparent,  and 
it  is  evident  that  injury  will  be  much  less  on  dry  upland  soil,  and 
much  more  severe  in  bottoms  where  the  cotton  grows  rank  and 

thick. 

Over  a  score  of  parasites  *  prey  upon  the  immature  stages 
within  the  squares  or  bolls,  and  they  seem  to  be  increasing  in  num- 
bers and  effectiveness  as  they  become  adapted  to  hving  upon  the 
weevil,  as   they  are  all  native  insects  which   prey  upon   nearly 


Fig.  198. — Cluiin  cultivator  for  use  in  drawing  weevil  infested  squares  to  center 
of  row.     (After  Hunter,  U.  S.  Dept.  Agr.) 

related  species  of  weevils  and  other  insects.  Ac  many  as  two-thirds 
of  the  immature  stages  have  been  destroyed  by  them  in  certain 
fields,  though  ordinarily  not  over  5  per  cent  of  the  total  are  para- 
sitized. Several  species  of  ants  also  feed  on  the  immature  stages, 
20  to  30  per  cent  of  those  in  fallen  squares  and  Ijolls  often  being 
destroyed  by  them.  The  ants  destroy  many  more  in  the  fallen 
squares  than  in  those  hanging  on  the  plants,  so  that  the  dropping 
of  the  squares  aids  their  good  work  as  well  as  exposes  the  squares 
to  the  heat  of  the  sun. 

Usually  about  70  per  cent  of  the  infested  squai-es  drop,  and  in 
tjiese  70  to  80  per  cent  of  the  immature  stages  are  destroyed  by 
natural  causes. f 

*  See  W.  D.  Pierce,  Studies  of  Parasites  on  the  Cotton  Boll  Weevil, 
Bulletin  73,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 

t  See  W.  E.  Hinds,  Some  Factors  in  the  Natural  Control  of  the  Mexican 
Cotton  Boll  Weevil,  Bulletin  74,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO   COTTON 


269 


Control. — B}^  far  the  most  important  measure  in  the  control  of 
the  boll  weevil  is  the  destruction  of  the  plants  in  the  fall  as 
soon  as  the  cotton  can  be  picked. 
This  both  destroys  the  weevils 
and  prevents  their  increase.  The 
stalks  should  be  plowed  out  and 
burned  as  soon  as  possible.  It  is 
well  to  plow  out  all  l)ut  a  row 
here  and  there  upon  which  the 
weevils  will  concentrate,  then  as 
soon  as  the  piles  are  dry  enough 
to  burn,  cut  the  remaining  rows 
and  burn  at  once.  In  this  way  the 
great  bulk  of  the  adult  weevils 
and  all  of  the  immature  stages 
in  the  squares  and  bolls  are 
destroyed.  The  few  escaping  wee- 
vils will  be  starved  out  before  the 
weather  becomes  cold  enough  for 
them  to  hibernate,  or  will  be  so 
weakened  as  to  die  in  hibernation. 
Professor  Wilmon  Newell,  in  Louisiana,  that  where  the  weevils 
were  forced  into  hibernation  on  October  15th  only  3  per  cent 
survived  the  winter,  but  that  when  the  destruction  of  the  stalks 
was  put  off  until  after  December  15th,  43  per  cent  survived,  with 
proportional  numbers  at  intervening  dates.  Furthermore,  the 
development  of  the  late  broods  which  furnish  the  majority  of  the 
weevils  which  hibernate  is  effectually  prevented.  The  removal 
of  the  plants  also  facilitates  winter  plowing,  which  aids  in  produc- 
ing an  early  crop  the  next  year.  Many  experiments  and  the 
experience  of  practical  planters  have  shown  that  the  destruction  of 
the  stalks  in  the  fall  is  of  primary  importance  in  the  control  of  the 
weevil,  particularly  upon  bottom  lands.  Experiments  made  in 
Calhoun  County,  Texas,  where  the  stalks  were  destroyed  on  410 
acres,  showed  an  increase  the  next  season  of  over  one-quarter 
bale  per  acre  as  compared  with  fields  where  the  stalks  had  been 


Fig.  199. — Solenopsis  geminata 
Fab!,  a  native  ant  which  is  a 
valuable  enemy  of  the  boll 
weevil — much  enlarged.  (After 
Hunter  and  Hinds,  U.  S.  Dept. 
Agr.) 

Thus  it  has  been  shown  by 


270      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

left  standing,  the  benefit  being  worth  $14.56  per  acre,  or  over 
twenty-nine  times  the  cost  of  the  work.  It  is  l^etter  to  plow  out 
the  stalks  than  to  cut  them,  particularly  in  the  far  South,  as  the 
stalks  will  frequently  sprout  out  in  the  late  fall  and  thus  furnish 


Fig.  200. — Bracon  mellitor  Say,  one  of  the  most  important  parasites  of  the 
boll  weevil  larvie — much  enlarged.  (After  Hunter  and  Hinds,  U.  S. 
Dept.  Agr.) 

food  for  the  late  weevils,  or  will  sprout  in  early  spring  and  furnish 
food  for  those  first  emerging  from  hibernation.  For  the  same 
reasons  all  volunteer  cotton  should  be  destroyed. 

It  is  evident  that  the  thorough  defoliation  of  the  plants  by  the 
cotton  leafworm  will  secure  much  the  same  result  as  the  destruc- 
tion of  the  stalks,  by  removing  the  food  supply  of  the  weevil. 
Planters  should  not  poison  the  leafworms,  therefore,  when  they 
appear  during  the  latter  part  of  the  season  in  fields  injured  by  the 
weevil,  for  though  formerly  much  dreaded  they  are  now  a  great 
aid  in  preventing  the  increase  of  the  weevil  in  fall. 

It  has  been  demonstrated  that  injury  by  the  weevil  is  never  so 
severe  where  cotton  is  planted  after  some  other  crop,  this  being 
due  to  the  fact  that  the  weevils  do  not  fly  far  from  their  hibernating 
quarters  in  the  spring. 


INSECTS  INJURIOUS  TO  COTTON  271 

By  hastening  the  maturity  of  the  crop,  injury  Ijy  the  weevils 
may  be  avoided  by  making  the  crop  before  they  have  become 
most  abundant.  Everything  possible  should  therefore  be  done 
toward  hastening  maturity,  and  this  will  be  of  importance  in  rela- 
tion to  the  early  destruction  of  the  stalks  in  the  fall.  Land  should 
be  plowed  in  the  winter  and  a  good  seed  bed  prepared.  Cotton 
should  be  planted  as  early  as  possible  with  safety.  A  liberal  use 
of  commercial  fertilizers  will  hasten  the  growth  of  the  crop  even  on 
fairly  fertile  soils,  and  on  poor  soils  their  use  will  return  a  hand- 
some profit.  Early  varieties  of  cotton  should  be  planted,  among 
the  most  satisfactory  being,  Rowden,  Triumph,  Cleveland  Big 
Boll,  Cook's  Improved,  King,  Hawkins'  Early  Prolific,  and  Sim- 
kins.  Seed  should  be  secured  from  the  originators  of  the  varie- 
ties as  far  as  possible.  Chop  out  the  plants  as  soon  as  possible. 
Frequent  light  cultivation  will  be  found  of  the  greatest  importance 
in  hastening,  the  crop.  Deep  cultivation  and  cultivating  close  to 
the  plants  shovild  be  avoided  as  causing  the  squares  to  shed,  and 
the  old  practice  of  ^'  laying  by  "  by  running  a  broad  sweep  down 
the  middles  should  l)e  avoided.  The  lightest  possible  cultivation 
to  keep  the  surface  soil  stirred  is  the  best.  All  of  these  methods 
which  aid  in  hastening  the  maturity  of  the  crop  are  commonly 
called  "  cultural  methods  "  of  preventing  loss  from  the  weevil. 
They  are  not  directed  against  the  weevil  itself,  but  are  merely  the 
best  agricultural  methods  for  securing  an  early  crop,  and  on  light 
upland  soils  attention  to  these  methods  will  alone  be  sufficient  to 
secure  a  good  crop. 

It  has  already  been  shown  that  the  immature  stages  in  squares 
falling  on  the  hot  soil  will  be  killed  by  the  heat.  To  aid  in  this 
the  rows  should  be  planted  fairly  wide  apart,  and  vai'ieties  pro- 
ducing a  minimum  of  shade  are  preferable,  as  are  those  which 
readily  shed  their  squares  when  injured.  As  most  of  the  squares 
drop  beneath  the  plants  where  they  are  shaded,  any  means  of 
scraping  them  into  the  centres  of  the  rows  will  aid  in  their 
destruction.  For  this  purpose  a  chain  cultivator  as  described  by 
Hunter  (I.e.)  (Fig.  198)  has  proven  very  efficient  for  this  purpose. 
The  chains  may  be  attached  to  ordinary  cultivators  by  special 


272       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

attachments.  An  arm  or  projection  that  will  brush  the  plant 
should  be  attached  to  whatever  cultivator  is  used  so  that  the 
squares  will  be  knocked  to  the  ground,  as  the  effect  of  the  heat  is 
greater  the  earlier  the  squares  drop. 

During  1909  Professor  Wilmon  Newell  and  his  assistants  demon- 
strated at  several  places  in  Louisiana  that  the  weevil  may  be  suc- 
cessfully poisoned  by  the  use  of  dry  or  powdered  arsenate  of  lead, 
though  previous  experiments  with  dry  Paris  green  and  arsenate 
of  lead  as  a  liquid  spray  had  not  proven  of  practical  value  for  vari- 
ous reasons.  An  increase  of  71  per  cent  of  the  crop  was  secured 
on  considerable  areas  and  the  results  were  duplicated  b}-  practical 
planters.  Professor  Newell  recommends  that  the  poison  be 
applied  first  when  the  first  squares  appear  and  that  five  appli- 
cations be  given  at  weekly  intervals.  The  poison  must  be 
applied  by  hand  with  a  powder-gun  so  that  it  is  blown  into  the 
squares.  The  first  application  requires  about  2^  pounds  per  acre 
and  the  last  5  to  7  pounds.  The  cost  for  labor  and  materials  will 
amount  to  from  $5  to  $7  per  acre,  but  at  this  rate  the  operation 
will  show  a  decided  profit  with  the  above  amount  of  benefit  as 
long  as  cotton  sells  at  over  8  cents  per  pound.  Although  the  use 
of  powdered  arsenate  of  lead  is  still  in  an  experimental  stage,  it 
promises  to  become  one  of  the  most  important  means  of  com- 
bating the  boll  weevil,  particularly  in  the  river  bottoms  of  the 
Mississippi  basin,  where  conditions  for  the  multiplication  and 
hibernation  of  the  weevil  arc  particularly  favorable.* 

*  See  Newell  and  Smith,  Circular  33,  Louisiana  Crop  Pest  Commission, 
Baton  Rouge,  La. 


CHAPTER  XIV 

INSECTS  INJURIOUS  TO  THE  HOP-PLANT  * 

The  Hop-plant  Borer  t 

The  Hop-plant  Borer  is  sometimes  the  occasion  of  a  consider- 
able loss  to  the  hop  industry,  Mr.  Chas.  R.  Dodge  having  estimated 
upon  the  basis  of  the  census  of  1879  that  it  then  amounted  to 
$600,000  annually  in  Xew  York  State  alone.  The  moths  have 
been  taken  from  Ontario  and  New  England  south  to  the  District 
of  Columbia,  and  west  to  AVisconsin,  and  also  from  Colorado  and 
Washington,  but  the  larvie  have  never  become  injurious  in  the 
hop-fields  of  the  Pacific  Coast.  ''  It  is  prol^able  that  it  is  a  north- 
ern form,  and  confined,  as  it  seems  to  be,  to  a  single  food-plant,  it 
will  l:)e  found  only  where  this  plant  is  known  to  grow." 

Life  History. — Many  of  the  moths  emerge  from  the  pupae  in  the 
fall  and  hibernate  over  winter,  while  others  do  not  transform  till 
spring,  passing  the  winter  in  the  pupal  stage  in  small  cells  in  the 
ground  near  the  roots  of  the  plant  which  the  larvse  have  infested. 
The  moths  appear  during  May,  and  the  females  deposit  their  globu- 
lar, yellowish-green  eggs  upon  the  tips  of  the  hop-vines  just  as  they 
begin  to  climb.  "  The  egg  hatches  in  a  few  days  and  produces  a 
minute  slender  greenish  larva,  spotted  with  black,  which  immedi- 
ately burrows  into  the  vine  j  ust  below  the  tip,  and  spends  a  part  of 
its  life  in  the  vine  at  this  point.  The  vine  soon  shows  the  effects  of 
the  insect's  work;  instead  of  pointing  upward,  embracing  the  pole 
readily  and  growing  rapidly,  the  tip  points  downward,  will  not 
climb,  and  almost  entirely  ceases  growing.  This  appearance  is 
called  by  growers  a  '  muffle-head.'     When  the  insect  attains  a 

*  "  Some  Insects  Affecting  the  Hop-plant,"  L.  O.  Howard,  Bulletin  No. 
7,  n.  s.,  Division  of  Entomology,  U.  S.  Dept.  Agr.,  p.  41. 
t  Hydroecia  immanis  Grt.     Family  Noctuidoe. 

273 


274 


INSECTS    INJURIOUS  TO  THE  HOP-PLANT 


length  of  about  half  an  inch,  or  slightly  less,  it  leaves  the  tip,  drops 
to  the  ground,  and  entering  the  stem  at  the  surface  of  the  vine, 
feeds  upward,  'nterrupting  the  growth  of  the  vine  and  lessening  its 
vitality;  the  larva  now  changes  color,  and  becomes  a  dirty-white, 
with  a  strong,  deep  reddish  tint,  with  numerous  black  spots.  The 
larva,  now  about  an  inch  in  length,  and  still  slender,  burrows  down- 
ward to  the  base  of  the  vine  at  its  juncture  with  the  old  stock,  and 
eating  its  way  out,  completes  its  growth  as  a  subterranean  worker; 


Fig.  201. — Hop-plant  borer  (Hydroecia  immanis  Grt.):  a,  enlarged  segment  of 
larva;  h,  larva;  c,  pupa;  d,  adult,  natural  size.  (After  Howard,  U.  S. 
Dept.  Agr.) 


it  is  in  this  state  that  it  is  best  and  most  widely  known  as  the  hop 
'  grub,'  and  the  ravages  caused  l)y  it  are  most  noted."* 

The  larva)  have  mostly  left  the  stems  by  the  last  of  June 
and  henceforth  are  mainly  sap-feeders.  Eating  into  the  stem 
just  below  the  surface  of  the  ground  and  just  above  the  old  root, 
they  rapidly  grow  fat  upon  the  juices  of  the  plant.  These  openings 
are  gradually  enlarged  so  that  very  often  the  stem  is  entirely 
severed  from  the  root  or  is  so  slightly  attached  that  the  plant 
is  badly  stunted  and  yields  few,  if  any,  hops.  The  larvaj  become 
full  grown  from  the  middle  to  the  20th  of  July  and  are  then 

*  "  Hop-insects,"  Dr.  J.  B.  Smith,  Bulletin  No.  4,  o.  s.,  Division  of  Ento- 
mology, U.  S.  Dept.  Agr. 


INSECTS   INJURIOUS  TO   THE  HOP-PLANT  275 

"  about  two  inches  in  length,  fleshy,  unwieldy,  and  very  slow  in 
their  movements;  they  are  of  a  dirty  white  color,  speckled  with 
fine,  brownish  elevated  tubercles,  each  furnished  with  a  single 
stout  hair;  the  head  is  brownish  and  corneous,  as  is  also  the  top 
of  the  first  segment."     (I.e.) 

The  larva)  now  transform  to  pupa?  in  rough  cells,  close  to  the 
roots  which  they  have  infested,  and  the  adult  moths  emerge 
during  August  or  September,  or  the  following  spring.  The 
adult  moths  are  found,  upon  close  examination,  to  be  most 
beautifully  marked,  though  not  of  a  striking  appearance  at  first 
sight.  "  The  general  color  is  a  rosy  brown,  paler  at  the  extremity 
of  the  wings.  The  darker  central  portion  is  shaded  with  dark 
velvety  bronze  and  marked  with  two  dull-yellow  spots.  The  fore- 
wings  are  divided  into  three  areas  by  narrow  oblique  transverse 
lines,  edged  outwardly  with  pink.  The  hind-wings  are  paler  in 
color,  crossed  in  the  middle  by  a  slightly  darker  line." — Howard  I.e. 

Remedies. — Two  points  in  the  life  history  of  the  insect  afford 
opportunity  for  its  control.  The  first  is  when  the  young  larvae 
are  still  in  the  tips  and  can  easily  be  crushed  by  the  fingers  when 
tying  the  vines.  "  Muffleheads  "  should  always  be  picked  off 
and  destroyed. 

Early  in  June  when  the  larvae  have  left  the  inside  of  the  vines 
it  is  well  to  remove  all  the  soil  from  the  base  of  the  vine,  down 
to  the  junction  with  the  old  root.  The  larva?,  which  will  not 
feed  above  ground,  will  go  to  the  old  roots,  to  which  they  will 
do  but  little  injury.  The  roots  should  be  left  thus  exposed  for 
about  a  week.  A  handful  of  mixture  of  coal  and  wood  ashes  or 
ammoniated  phosphate  should  then  be  applied  to  each  and  the 
plants  hilled  high.  The  plant  will  now  send  out  new  rootlets 
from  the  main  root,  and  is  able  to  secure  necessary  nourishment 
through  them. 

The  Hop-louse  * 

Like  many  another  aphid  the  Hop-louse  has  a  most  interest- 
ing life  history,  which  has  been  fully  ascertained  in  but  recent 
years.     During  the  winter  the  small  oval  black  eggs  may  be 
*  Phorodon  humuli  Schr.     Family  Aphididoe. 


276         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

found  ill  the  crevices  and  ai-ouiid  the  Imd.s  of  the  terminal  twigs 
of    plum-trees   near   infested    hop-fields.     From   these   hatch    a 


Fig.  202. — The  hop-louse  (Phorodon  humuli  Schr.) :  a,  winter  eggs  and  shrivelled 
skin  of  the  sexual  female  which  laid  them;  b,  stem-mother,  or  fu-st  spring 
generation,  with  enlarged  antenna  above — all  much  enlarged.  (After 
Riley,  U.  S.  Dept.  Agr.) 


Fig.  203. — The  hop  plant-louse,  third  generation  on  plum— the  generation 
which  flies  to  the  hop — enlarged;  head  below  at  right — still  more 
enlarged.     (After  Riley,  U.  S.  Dept.  Agr.) 

generation  of  females,  known  as  "  stem-mothers,"  during  the 
following  spring.  The  aphides  of  this  generation  differ  in  being 
stouter,  with  shorter  legs  and  honey-tubes  than  those  of  any  other 


INSECTS  INJURIOUS  TO   THE  HOP  PLANT 


277 


generation.      Three  generations  feed   upon  the  plum,  the  third 
becoming  winged  and  flying  to  its  favorite  food   in  the  hop-field. 

Throughout  the  summer  the  aphides  reproduce  partheno- 
genetically.  They  "  multiply  with  astonishing  rapidity  for 
from  five  to  twelve  generations,  carrying  us  in  point  of 
time  to  the  hop-picking  season."  "  Each  parthenogenetic 
female  is  capable  of  producing  on  an  average  one  hundred 
young  (the  stem-mother  probably  being  more  prolific),  at  the 
rate  of  one  to  six,  or  an  average  of  three 
per  day,  under  favorable  conditions. 
Each  generation  begins  to  breed  about 
the  eighth  day  after  birth,  so  that  the 
issue  from  a  single  individual  easily  runs 
up,  in  the  course  of  the'summer,  to  mil- 
lions. The  number  of  leaves  (700  hills, 
each  with  two  poles  and  two  vines)  to  an 
acre  of  hops,  as  grown  in  the  United 
States,  will  not,  on  the  average,  much 
exceed  a  million  before  the  period  of 
blooming  or  burning;  so  that  the  issue 
from  a  single  stem-mother  may,  under 
favoring  circumstances,  blight  hundreds 
of  acres  in  the  course  of  two  or  three 
months."  * 

During  September  a  brood  of  winged  females  are  produced 
which  fly  back  to  the  plum-trees,  and  in  the  course  of  a  few  days 
give  birth  to  three  or  more  young.  These  never  become  winged, 
but  are  the  true  sexual  females  which  lay  the  winter  eggs.  The 
true  winged  males  are  developed  during  the  latter  part  of  the 
season  and  may  be  found  pairing  with  the  wingless  females  at 
that  time,  these  being  the  only  males  during  the  year. 

Remedies. — From  a  knowledge  of  the  above  life  history 
several  methods  of  treatment  have  been  devised.  By  spraying 
plum-trees  neighboring  the  hop-yard  and  infested  with  aphides 
while   they   are  laying   the   eggs,   during  fall   or   in  the   spring 

*  Riley,  The  Hop-louse,  Insect  Life,  Vol.  I,  p.  135. 


Fig.  204.—  The  hop 
plant-louse,  true  sex- 
ual female — enlarged. 
(After  Riley,  U.  S. 
Dept.  Agr.) 


278       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

before  the  winged  generation  appears,  with  some  substance 
which  will  destroy  them,  the  pest  may  be  prevented  from  getting 
a  start  the  next  season.  Sprajdng  the  trees  during  the  fall  is 
best,  because  a  stronger  or  more  caustic  solution  can  then  be 
applied  without  danger  of  injury  to  the  tree.  A  winter  wash  of  1 
pound  of  concentrated  lye  to  2  gallons  of  water  may  be  used  as  a 
spray  to  advantage  in  killing  a  large  share  of  the  eggs,  but  should 
not  be  applied  after  the  buds  commence  to  swell  in  the  spring.   To 


Fig.  205. — The  hop  plant-louse,  male — enlarged.  (After  Riley,  U.  S.  D.  Agr.) 

lessen  the  number  of  eggs  all  wild  plum-trees  in  the  neighboring 
woods  should  be  destroyed.  As  soon  as  the  crop  is  harvested, 
the  hop-vines  should  be  burned  or  thoroughly  sprayed  with 
kerosene  emulsion,  so  as  to  kill  off  the  males  before  they  have 
been  able  to  fertihze  the  females. 

For  spraying  the  plum-trees  and  hop-vines  kerosene  emulsion 
has  been  found  very  satisfactory,  diluting  the  stock  solution  with 
15  parts  of  water. 

Fish-oil  or  whale-oil  soap  used  at  the  rate  of  1  pound  to  8 
gallons  of  water  will  prove  an  effective  spray  against  the  lice. 
Also  see  page  664. 


INSECTS  INJURIOUS  TO  THE  HOP-PLANT 


279 


The  Hop-vine  Snout-moth  * 

The  larvsB  of  the  Hop-vine  Snout-moth  sometimes  become 
very  formidable  pests  in  the  hop-field,  appearing  suddenly  in 
large  numbers  and  rapidly  eating  the  foliage  over  a  large  area. 

They  are  not  known  to  have  any  other  food-plant  than  the 
hop  and  hence  are  only  found  where  that  plant  occurs,  though 
specimens  have  been  taken  from  almost  all  sections  of  the  United 
States,  southern  Canada,  and  British  Columbia. 


Fig.  206. — The  hop-\'ine  snout-moth  (Hypena  hiwiuli  Harr.):  a,  egg;  b,  larva 
c,  segment  of  same;  d,  pupa;  e,  cremaster  of  same;  /,  adult — o,  c,  e, 
greatly  enlarged,  others  slightly  enlarged.  (After  Howard,  U.  S.  Dept. 
Agr  ) 


Life  History. — It  seems  probable  that  the  moths  hibernate 
over  winter,  as  they  emerge  in  the  fall,  and  lay  eggs  for  the  first 
brood  early  in  the  following  May.  The  eggs  are  of  a  pale  green 
color,  and  are  deposited  upon  the  under  surfaces  of  the  leaves, 
sometimes  several  upon  a  single  leaf.  The  larvae  emerging  from 
them  l^ecome  mature  late  in  June  and  early  in  July.  When 
full-grown  the  larvae  are  slightly  less  than  one  inch  long,  and 
"  of  a  green  color,  marked  with  two  longitudinal  white  lines  down 
the  back,  a  dark-green  line  in  the  middle  between  and  an  indistinct 
whitish  line  on  each  side  of  the  body.     The  head  is  green,  spotted 

*  Hypena  humuli  Harr.     Family  NoctuidoE. 


280       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

with  black  piliferous  dots,  autl  similar  dots  occur  on  each  seg- 
ment, arranged  in  two  transverse  rows."  * 

Before  pupating  the  larva  spins  a  thin  silken  cocoon,  either 
among  the  leaves,  under  the  bark  of  the  poles,  or  at  or  slightly 
under  the  surface  of  the  ground.  The  pupal  stage  occupies  about 
ten  days,  and  the  moths  emerge  from  the  cocoons  early  in  July. 
Another  brood  follows  with  a  similar  life  history,  the  moths 
emerging  late  in  August  and  in  September  and  probably  hibernat- 
ing over  w^inter. 

The  larvse  are  known  as  "  false  loopers,"  on  account  of  their 
bending  the  back  slightly  in  creeping,  which  is  due  to  their  lacking 
the  first  pair  of  pro-legs. 

Another  species  of  the  same  genus  (Hypena  rostralis)  affects 
hop-vines  in  Europe  in  the  same  manner  and  is  very  similar  to 
the  one  above  described. 

Remedies. — The  larvae  can  be  controlled  by  the  use  of  any 
arsenical  spray,  which  should  be  applied  while  they  are  still  young. 

Hop-merchants 

The  so-called  "Hop-merchants,"  which  here  and  there  gleam 
from  the  vines  are  the  chrysalids  of  two  common  butterflies,  whose 
larvae  feed  preferably  upon  hops.  The  chrysalids  are  normally 
marked  with  beautiful  gold  or  silver  spots,  which  sometimes 
become  so  diffused  as  to  tinge  the  whole  chrysalis.  "  An  inter- 
esting superstition  holds  among  hop-growers  to  the  efftn-t  that 
when  the  golden-spotted  chrysalids  are  plentiful  the  crop  will 
he  good  and  the  price  high,  while  if  the  silver-spotted  ones  are 
plentiful  and  the  golden-spotted  ones  are  scarce  the  price  will  be 
low." — Howard,  (I.e.). 

The  Semicolon-butterfly  f 

The  common  names  of  these  two  butterflies  indicate  the  most 
striking  mark  of  distinction  between  them.  P.  interrogationis 
bears  a  silver  mark  like  a  semicolon  or  interrogation  point  upon 

*  Howard,  I.e. 

j"  Polygonia  interrogationis  Godart.     Family  Nymphalidoe. 


INSECTS  INJURIOUS  TO  THE    HOP-PLANT 


281 


the  under  side  of  the  hind  wings  (Fig.  207),  while  P.  comma  has  the 
same  mark  without  the  dot,  which  thus  resembles  a  comma 
(Fig.  208). 

The  Semicolon-butterfly  is  common  throughout  the  United 
States  east  of  the  Rockies,  and  especially  in  hop-growing  regions. 
It  hibernates  over  winter  and  is  among  the  first  butterflies  to  be 
seen  in  early  spring,  when  it  is  often  attracted  to  the  flowing  sap 


a 


YiG.  207. — The  semicolon-butterfly  (Polygonia  interrogationis) :  a,  egg-chain; 
b,  larva;  c,  chrysahs;  J,  adult — all  natural  size  excejjt  a,  which  is 
greatly  enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 


of  newly  cut  trees.  The  eggs  are  laid  late  in  May  or  early  in  June, 
usually  upon  the  under  surface  of  the  leaves  of  elm,  blackberry, 
or  nettle,  either  singly  or  in  pendent  columns  of  from  two  to 
eight.  They  hatch  in  from  four  to  eleven  days  and  the  larvae 
grow  quite  rapidly. 

When  full  grown  the  larva  is  an  inch  and  a  ([uartcr  long.  The 
head  is  reddish-black,  somewhat  bilobed,  each  lobe  being  tipped 
with  a  tubercle  bearing  five  single,  black-pointed  spines,  and  cov- 
ered with  many  small  white  and  several  lilackish  tubercles.     The 


282        INSECT  PESTS  OF   FARM,    GARDEN  AND  ORCHARD 

body  is  black,  thickly  covered  with  streaks  and  dots  of  yellowish 
white;  the  second  segment  is  without  spines,  but  with  a  row  of 
yellowish  tubercles  in  their  place;  the  third  segment  has  four 
branching  spines,  all  black,  with  a  spot  of  dark  yellow  at  their 
base;  and  on  the  fourth  segment  are  four  spines,  as  there  are  on  all 
the  others,  excepting  the  terminal,  which  has  two  pairs,  one  pos- 
terior to  the  other.  The  spines  are  yellow,  with  blackish  branches, 
excepting  the  terminal  pair,  which  are  black;  and  there  is  a  row  of 
reddish  ones  on  each  side.  The  under  surface  is  yellowish  gray, 
darker  on  the  anterior  segments,  with  a  central  line' of  blackish, 
and  many  small  black  dots. 

The  chrysalis  is  ash-brown,  with  the  head  deeply  notched,  and 
with  eight  silvery  spots  on  the  back;  this  stage  lasts  from  eleven 
to  fourteen  days  and  the  butterflies  emerge  in  July.  These  lay 
eggs  for  another  brood  late  in  July  and  throughout  August,  mainly 
upon  the  hop-plants,  where  they  are  to  be  found.  When  the  cater- 
pillars of  this  brood  are  numerous  they  sometimes  do  considerable 
damage  to  the  foliage,  but  both  this  and  the  following  species  are 
ordinarily  prevented  from  becoming  ovcrnumerous  by  several 
parasites  of  the  eggs  and  larvae.  Only  when  for  some  reason  con- 
ditions are  unfavorable  to  the  development  of  its  parasites  does 
either  species  become  especially  abundant.  In  fact,  Dr.  J.  B. 
Smith,  who  made  extensive  observations  upon  hop-insects  in  1883. 
states  "  that  not  one  in  ten  of  the  insects  ever  attains  the  butterfly 
state." 

The  chrysalis  stage  of  the  second  brood  is  somewhat  longer 
than  the  first,  sometimes  lasting  twenty-six  days,  and  the  butter- 
flies emerge  from  the  latter  part  of  August  until  the  end  of  October, 
and  at  once  seek  quarters  in  which  to  hibernate  over  winter. 

Both  this  species  and  P.  comma  are  dimorphic,  the  winter  and 
summer  forms  differing  in  both  sexes  in  both  the  upper  and  lower 
aspects  of  the  wings.  In  the  South,  where  from  three  to  five 
broods  occur  in  a  season,  both  forms  are  usually  found  in  the  sec- 
ond and  third  broods,  the  summer  form,  var.  u7nbrosa,  gradually 
decreasing  until  all  of  the  fourth  brood  are  the  hibernating  winter 
form,  var.  fabricii. 


INSECTS  INJURIOUS  TO  THE  HOP-PLANT 


283 


The  Comma-butterfly  * 

The  Comma-butterfly  is  most  common  throughout  the  East 
from  New  England  to  North  CaroHna  and  Tennessee,  though  occa- 
sionally found  as  far  west  as  Wisconsin,  Iowa,  Nebraska,  and 
Texas. 


Fig.  208. — The  comma-butterfly  (Polygonia  comma):  a,  egg-chain;  b,  larva; 
c,  chrysaUs;  d,  adult — all  natural  size,  except  a.  which  is  greatly 
enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 


Its  life  history  is  practically  the  same  as  that  of  the  species  just 
described.  The  larvse  of  the  first  brood  sometimes  seriously  dam- 
age young  elm-trees  which  have  been  but  recently  reset,  by  eating 
them  bare  of  the  foliage.  The  winter  form  hibernates  about  a 
month  earlier,  being  rarely  seen  in  October.     As  a  rule  a  similar 

*  Polygonia  comma  Harr.     Family  Nymphalidce. 


284        INSECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 

dimorphism  Occurs,  the  hibernating  form  being  known  as  var,  haV' 
risii  and  the  summer  form  var.  dryas,  though  the  distinction  is  not 
as  marked  in  this  species. 

Tlie  half-grown  hirva  is  l)k^ck,  with  a  yellowish  stripe  along  the 
side  from  the  third  segment,  and  with  j^ellow  stripes  across  the 
back,  and  spots  of  the  same  color  at  the  base  of  the  dorsal  spines, 
which  are  yellow  tipped  with  black.  The  mature  caterpillar  is 
white,  mottled,  or  striped  with  gray  or  ashen,  and  with  red 
spiracles. 

The  ])utt(M-flies  of  both  species  are  of  a  rich  ])rown  color,  marked 
with  ])lack  and  tipix'd  with  lilac  a])ove,  and  of  a  nuicli  darker  pur- 
plish brown  with  the  characteristic  sih'er  s2)ots  beneath,  which  are 
well  indicated  in  the  illustration. 

Remedies. — Spraying  with  an  arsenical  will  destroy  the  larvaB 
when  such  treatment  becomes  necessary. 


CHAPTER   XV 
INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES 

The  Potato  Stalk-borer  * 

In  some  sections  this  insect  has  rivaled  the  famous  Colorado 
potato-l3ug  in  the  damage  it  has  inflicted  upon  potato-vines.  It 
was  recorded   as   badly   damaging  the    crop   in   Iowa  in   1890, 


Fig.  209. — Work  of  potato  stalk-borer  in  potato-vines.     (After  J.  B.  Smith.) 

and  was  found  by  Dr.  Riley  in  Missouri  as  early  as  1869.     The 

beetles  were  first  noted  in  New  Jersey  in  1895,  and  have  been 

injurious  in  Maryland  and  most  of  the  Middle  States. 

Life  History. — The  grubs,  which  bore  into  the  stalks  of  the  vines, 

*  Trichobaris  trinotata  Say.     Family  Curcidiomdae. 

285 


286     INSECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 

are  the  larvae  of  some  small  ashen-gray  beetles  which  appear  early 
in  spring  and  into  June.  These  beetles  are  about  one-fourth  of  an 
inch  long,  with  a  long,  black  beak  or  snout,  and  are  marked  at  the 
base  of  the  wing-covers  by  three  black  spots  which  give  the  insect 
its  specific  name,  trinotata.  Each  beetle  punctures  a  small  hole  in 
the  base  of  a  stem  by  means  of  its  beak,  hollows  out  a  small  cavity, 
and  there  lays  a  single  small,  oval,  whitish  egg.  From  these  eggs 
some  small,  white  grubs  with  brown  heads  hatch  in  a  few  days  and 
commence  to  bore  into  the  stalk.  These  grubs  keep  eating,  either 
in  the  main  stalk  or  branches,  from  August  1st  to  September  1st, 


Fig.    210. — Potato    Stalk-borer   (Trichobaris   trinotata). 
adult.     (After  J.  B.  Smith.) 


Larva,    pupa  and 


when  they  have  l^ecome  full  grown.  At  this  time  the  grubs  are 
about  one-half  an  inch  long,  of  a  dirty  white  or  yellowish  color, 
with  a  yellowish-brown,  horny  head,  and  without  legs.  About  the 
middle  of  August,  as  a  general  rule,  the  grubs  construct  small,  oval 
cocoons  of  chips  and  fibres  in  the  stalk  of  the  vine  near  the  sur- 
face of  the  soil,  and  there  transform  to  the  pupa.  During  late 
August  and  September  the  mature  beetles  shed  the  pupal  skins,  in 
which  they  have  remained  dormant  for  the  last  few  weeks,  but 
remain  in  the  vines  during  the  winter,  and  do  not  come  forth  till 
the  following  spring. 

Remedies. — On  account  of  its  internal  feeding  habits  no  poison 
can  be  successfully  used  against  this  pest,  and  the  only  remedy, 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES  287 

but  a  good  one,  is  to  rake  up  the  vines  and  burn  them  as  soon  as 
the  potatoes  have  been  dug.  As  this  insect  also  feeds  upon  the 
Jamestown  weed,  horse-nettle,  and  other  weeds  of  the  Nightshade 
family,  or  Solanaccce,  they  should  be  kept  cut  down  very  closely. 
When  the  grubs  are  noticed  in  the  plants,  a  good  allowance  of  fer- 
tilizer will  do  much  to  quicken  growth  and  thus  enable  them  to 
mature  a  crop. 

The  Stalk-borer  * 

This  species  may  well  be  called  the  stalk-borer,  for  it  not  only 
tunnels  the  stalks  of  potatoes — being  often  called  the  potato  stalk- 
borer — and  tomatoes,  but  frequently  infests  corn,  cotton  and  a  long 
list  of  garden  crops,  grains,  grasses,  flowering  plants,  and  various 
common  weeds.  Apparently  the  latter,  such  as  ragweed,  cockle- 
bur  and  the  like,  are  its  normal  food  plants,  and  when  they  are 
destroyed  or  where  more  tender  cultivated  plants  are  near  by, 
it  attacks  whatever  is  available.  Two  or  three  nearly  related 
species  have  very  similar  habits. 

The  adult  moth  (Fig.  211)  is  a  fawn-gray  or  mouse  color,  with 
the  outer  third  of  the  fore-wings  paler  and  bordered  within  by  a 
whitish  cross-line. 

Life  History. — The  eggs  are  laid  in  the  fall  on  the  stems  of 
weeds  and  grasses,  in  masses  of  fifty  or  sixty,  near  the  ground, 
They  are  about  one-fiftieth  inch  in  diameter,  circular,  grayish 
in  color,  with  radiating  ridges.  They  hatch  in  late  May  in 
southern  Minnesota  and  the  young  caterpillars  at  once  commence 
to  mine  small  galleries  in  the  leaves  of  the  food  plants,  soon 
riddling  the  leaves.  In  a  few  days  they  work  down  to  the  bases 
of  the  leaves  and  enter  the  stalks,  which  they  tunnel  out  and  not 
infrequently  leave  one  plant  and  migrate  some  little  distance 
before  entering  another.  Infested  plants  are  readily  recognized 
by  the  wilting  of  the  parts  above  the  larva,  the  work  in  corn 
being  particularly  noticeable  and  having  given  the  local  name 
of  "  heart-worm."  The  larvse  become  full  grown  about  the 
first  of  August.     They  are  readily  recognized  by  the  peculiar 

*  Papaipema  nitella  Gn.     Family  Noctuidce. 


288 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


markings  of  the  body  (Fig.  211,  b).  The  larva  is  about  an  inch 
long  and  varies  from  purplish  to  whitish  brown,  and  is  marked 
with  five  white  stripes,  one  along  the  middle  of  the  back,  and  two 
on  each  side.  These  sides  stripes  are  absent  on  the  first  four 
segments  of  the  abdomen,  giving  the  larva  an  appearance  as  if 
it  had  been  pinched  or  injured  there.  As  the  larva  matures  the 
stripes  become  fainter.     When  ready  to  pupate  the  larva  cuts  a 


Fig.  211. — The  stalk-borer  {Papaipema  nitella  Gn.):  a,  adult;  b,  half-grown 
larva;  c,  mature  larva  in  burrow;  d,  side  of  one  of  its  segments:  e, 
pupa — all  slightly  enlarged.     (From  Chittenden,  U.  S.  Dept.  Agr.) 


hole  through  the  side  of  the  stalk,  and  then  transforms  to  the 
brown  pupa  in  the  lower  part  of  the  stalk.  The  pupal  stage  lasts 
about  two  or  three  weeks,  and  the  moths  emerge  in  late  August, 
there  being  but  one  generation  a  year. 

Usually  the  injury  to  crops  is  only  in  the  outer  rows,  to  which 
the  larvae  have  migrated  from  weeds  growing  along  the  edges, 
or  in  fields  which  have  been  weedy  in  early  spring,  or  where  the 
weeds  have  been  allowed  to  get  a  start  before  being  culti- 
vated  out. 


INSECTS  INJURIOITS    TO  POTATOES  AND  TOMATOES       289 

Control. — Fiom  llic  lite  liisloi'v  ami  habits  i(  is  obx-ious  tliat 
fleaii  farniiiii;-  is  the  cnly  iiicthod  of  effectual  control.  The 
destruction  of  weeds  and  fall  plowing  should  prevent  any  general 
injury.  Usually  the  injury  is  but  local,  and  fortunately  the 
caterpillars  are  attacked  by  numerous  parasites  which  aid  in 
their  control,  sometimes  to  the  extent  of  killing  70  per  cent  of 
them.  In  small  gardens  the  prompt  destruction  of  infested 
plants  will  prevent  the  caterpillars  from  migrating  to  others. 
Where  weeds  are  infested  in  or  near  a  crop  thej^  should  be  destroyed 
as  soon  as  cut,  for  if  left  on  the  ground  the  larva?  will  promptlj' 
migrate  to  the  nearest  plants.  Where  fields  are  kept  clean  of 
weeds  there  will  be  little  trouble.* 

The  Potato  Tuber-worm  f 

The  most  serious  pest  of  the  potato  in  California  is  the  Tuber- 
worm,  which  in  tol^acco  regions  of  the  Southern  States  is  known 
as  the  "split  worm  "  or  leaf-miner  (see  page  237).  Xot  infre- 
quently 25  per  cent  of  the  crop  is  lost  in  infested  regions  in 
California,  injury  occurring  both  in  the  fields  and  to  the  tubers 
in  storage.  As  the  pest  is  carried  in  the  potatoes  and  breeds  in 
storage  throughout  the  warm  winters  of  California,  and  when 
exported  across  the  Pacific,  it  is  necessary  to  closely  inspect 
potatoes  from  infested  regions.  Although  no  injury  to  potatoes 
has  occurnMl  outside  of  California,  and  though  the  insect  probably 
could  not  exist  in  the  Xorth,  it  may  well  be  guarded  against  in 
the  Southern  States,  where  it  is  a  common  tobacco  pest. J 

Moths  which  have  developed  from  larvae  working  in  stored 
potatoes  are  on  the  wing  when  young  potatoes  are  up,  and  lay 
their  eggs  at  the  base  of  the  leaves.  The  young  larvae  bore  into 
the  stalks,  often  causing  the  plants  to  wilt  and  die.     On  older 

*  See  Forbes,  23d  Report  State  Entomologist  of  Illinois,  p.  44;  Washburn, 
12th  Report  State  Entomologi.st  of  Minnesota,  p.  151 ;  Journal  Economic 
Entomology,  III,  p.  16.3;  Smith,  Report  X.  J.  Agr.  Exp.  Sta.  for  1905,  pp. 
5S4-5S7. 

f  Phthorimea  opercnlella  Zell.  See  W.  T.  Clarke,  Bulletin  1.35,  California 
Agr.  Exp.  Sta. 

JRecently  serious  injury  by  this  insect  has  been  reported  to  potatoes 
near  HaUettsville,  Texas. 


290       INSECT  PESTS  OF  FARM,  GARDEN  AND   ORCHARD 

plants  or  when  the  stalks  harden,  the  larva3  leave  the  stalks  and 
enter  the  tubers,  particularly  where  they  may  be  exposed.  Where 
potatoes  are  exposed  by  being  insufficiently  covered  the  moths 
will  lay  their  eggs  directly  upon  them,  as  they  also  do  upon 
potatoes  exposed  in  the  field  after  digging. 

Most  of  the  observations  upon  the  life  history  seem  to  have 
been  made  upon  the  insect  when  breeding  in  stored  potatoes. 
The  eggs  are  about  one-fiftieth  inch  long,  oval,  white,  and  laid 
singly  or  in  pairs,  about  the  eyes  of  the  potatoes,  or  in  similar 
rough  places,  where  they  are  seen  with  difficulty.  They  hatch 
in  a  week  or  ten  days,  and  the  young  larvae  are  about  one- 
twenty-fifth  inch  long  of  a  transparent  white  color.  The 
larvse  burrow  beneath  the  skin  and  bore  into  the  potatoes, 
filling  their  burrows  with  frass  and  excrement,  which  soon  give 
rise  to  various  rots  which  cause  the  destruction  of  the  tuber, 
already  rendered  unfit  for  food  by  the  burrows.  The  larvae 
become  full  grown  in  about  six  or  seven  weeks.  They  are  then 
about  a  half  inch  long.  The  head  is  dark  brown;  the  first 
segment  is  an  old  rose  color,  with  dark  brown  shield  on  the 
back;  the  second  segment  is  a  similar  clouded  pink;  while  the 
third  and  succeeding  segments  are  a  clouded  white,  often  becom- 
ing yellowish  or  greenish,  according  to  the  food  eaten.  The  full- 
grown  larva  returns  to  the  mouth  of  the  burrow  and  there  makes 
its  cocoon,  or  leaves  it  and  forms  the  cocoon  in  some  depression 
of  the  potato  or  in  some  crack  of  the  storage  vessel  or  in  a  fold 
of  the  bag.  The  cocoon  is  constructed  quite  differently  from 
that  of  most  moths  as  described  by  Mr.  Clarke.  The  larva  first 
makes  a  mat  of  silk  and  then  forms  an  outer  layer  to  the  surface 
of  which  particles  of  dirt  and  rubbish  adhere  so  that  the  cocoon 
is  well  concealed.  When  this  pocket-like  cocoon  is  finished  the 
larva  enters  it  and  closes  the  open  end  and  in  it  transforms  to 
the  pupa.  The  pupal  stage  lasts  about  two  weeks,  so  that  the 
complete  life  cycle  requires  from  nine  to  twelve  weeks,  there  being 
several  generations  during  the  year,  according  to  the  temperature. 

Control. — As  the  insect  breeds  on  various  common  weeds  of 
the  Nightshade  family  (Solonacece) ,  it  is  important  that  they  be 


INSECTS   INJURIOUS  TO  POTATOES  AND  TOMATOES        291 

destroyed  wherever  found.  Seed  potatoes  must  be  free  from  the 
larvtc,  or  they  will  soon  give  rise  to  moths  which  will  infest  a 
whole  field.  When  young  plants  are  found  wilting,  the  infested 
stalks  should  be  cut  and  destroyed  as  soon  as  possible  to  prevent 
the  further  development  and  spread  of  the  pest.  Care  should 
be  taken  in  cultivating  to  hill  up  the  soil,  or  thoroughly  cover 
the  tubers,  so  that  they  are  not  exposed.  After  digging,  the 
potatoes  should  not  be  left  exposed  in  the  field  any  longer  than 
is  absolutely  necessary  and  should  not  be  covered  with  the  tops 
to  shade  them,  as  is  often  done,  as  this  furnishes  a  shelter  for  the 
moths  and  induces  oviposition  upon  the  tubers.  Infested  fields 
should  have  the  stalks  and  all  rubbish  and  refuse  thoroughly 
raked  up  and  l^urned  as  soon  as  possible,  or  sheep  and  hogs  may 
be  turned  into  the  fields  to  destroy  the  stages  which  may  be 
left  in  the  vines  or  in  the  soil.  Where  fields  have  been  flooded 
for  two  or  three  weeks  after  the  crop  has  been  dug,  they  have 
been  entirely  freed  of  the  pest.  For  the  treatment  of  stored 
potatoes,  fumigation  with  carbon  bisulfide  in  a  tight  room 
seems  to  be  the  only  satisfactory  method.  This  should  be  done 
as  described  for  grain  insects  (see  page  57).  The  tubers  should 
be  fumigated  as  soon  as  stored,  and  the  treatment  should  be 
repeated  at  intervals  of  two  weeks,  four  or  five  fumigations 
being  recommended  to  entirely  free  the  potatoes  of  all  stages. 
Obviously  it  will  be  important  to  sort  over  infested  tubers  and 
remove  all  which  are  materially  injured  to  prevent  the  increase 
of  rot  in  others. 

Colorado  Potato-beetle  * 

First  and  foremost  among  the  enemies  of  the  potato-grower 
stands  the  Colorado  potato-beetle — the  insect  which  in  the  early 
seventies,  on  account  of  our  ignorance  of  it,  was  made  an  entomo- 
logical bugbear.  But  "  there's  no  great  loss  without  some  small 
gain,"  and  we  may  be  thankful  that  the  invasion  of  this  beetle 
also  brought  about  the  use  of  Paris  green,  an  insecticide  which  has 

*  Leptinotarsa  decemlineata  Say.  Family  Chrysomelidoe.  See  F.  II. 
Chittenden,  Circular  87,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


292        INSECT   PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

since  saved  niilli(jiis  upon  millions  of  dollars  to  the  Americau 
farmer.  Thus,  with  an  effectual  remed}-  which  is  now  used  where 
this  pest  occurs  as  regularly  as  potatoes  are  planted,  "  famiharity 
has  bred  contempt,"  and  to-da}-  we  have  but  little  fear  of  its 
attack. 

History. — As  is  pi'obably  known  to  most  of  the  older  genera- 
tion who  watched  its  spread  eastward,  the  Colorado  potato-beetle, 
as  its  name  indicates,  was  a  native  of  the  Rocky  Mountain  region, 
and  until  about  lS5o  was  satisfied  with  feeding  upon  various  com- 


FiG.  212. — The  Colorado  potato-beetle  (Lcptixotarsa  deccmluicala  Say.):  n, 
eggs;  b,  larva;  r,  pupa;  d,  beetle;  c,  elylr-a  or  wing-cover  of  beetle; 
/,  leg  of  beetle.     (After  Riley.) 


mon  weeds  of  the  same  genus  as  the  potato-plant,  principally 
Solan um  datura,  and  closely  allied  genera.  But  with  the  settle- 
ment of  this  country  and  the  introduction  of  the  Irish  potato, 
these  bugs  also  began  to  take  advantage  of  the  fruits  of  civilization 
and  transferred  their  feeding-grounds  from  the  roadside  to  the 
potato-patch,  and  rapidly  spread  eastward  from  one  to  another, 
as  well  as  being  transported  in  the  shipping  of  the  potatoes. 

Thus,  in  1859  they  had  reached  a  point  one  hundred  miles  west 
of  Omaha,  Neb. ;  five  years  later  they  crossed  the  Mississippi  into 
Illinois;  and  they  advanced  steadily  eastward  till  recorded  among 


INSECTS  INJURIOUS    TO  POTATOES  AND   TOMATOES     293 

the  Atlantic  States  in  1874.  Th-ough  slow  to  be  introduced  into 
some  few  sections  of  the  countiy,  it  is  safe  to  assert  that  this  pest 
may  to-day  be  found  almost  wherever  the  potato  is  grown  in  the 
United  States  or  southern  Canada. 

Life  History. — During  October  the  beetles  enter  the  earth  and 
there  hibernate  till  the  warm  sunshine  of  Api-il  or  May  brings 
them  forth.  As  soon  as  the  young  plants  appear,  the  female 
beetles  deposit  their  yellow^  eggs  upon  the  under  side  of  the  leaves 
near  the  tips,  each  female  laying  an  average  of  about  five  hundred 
eggs  during  the  course  of  a  month.  Meanwhile  the  beetles  have 
done  considerable  damage  by  eating  the  j'oung  and  tender  plants. 
In  about  a  week  there  hatch  a  horde  of 
very  small  but  very  hungry  larvae,  which 
fairly  gorge  themselves  with  potato- 
foliage  and  increase  in  size  with  astonish- 
ing rapidity.  In  two  and  a  half  to  three 
weeks,  after  having  eaten  an  amount  of 
food  out  of  all  proportion  to  their  size,  the  jtiq  213  —a  beak  of  m-e- 
larvse    become   full  grown,  and  enter  the        daceous  bug;  6,  Podi- 

earth,    where    they     form   smooth,    oval        sus  svinosus  V>^\U  c, 
'  ''  '  beak   oi  plant-feeding 

cells,  and  transform  to  pupse.     In  a  week        bug.     (After  Riley.) 

or    two  the   adult    beetles    emerge    from 

the  pupal  skins  and  after  feeding  for  a  couple  of  weeks,  deposit 
eggs  for  a  second  generation,  which  develops  in  the  same  way, 
and  the  beetles  from  which  hibernate  as  already  described. 
Throughout  the  territory  where  the  beetles  are  most  injurious 
there  are  two  generations  a  year,  but  further  south  there  is  evi- 
dence of  at  least  a  partial,  if  not  complete,  third  generation,  and 
in  the  northern  range  of  the  species  there  is  but  one  generation 
a  year. 

Natural  Enemies. — One  of  the  chief  agencies  to  prevent  the 
excessive  multiplication  of  this  pest  is  the  weather.  Thus,  Pro- 
fessor Otto  Lugger  records  that  in  Minnesota,  late  in  the  fall 
of  1894,  the  beetles  were  lured  from  their  winter  quarters  by  a 
few  warm  days,  and  most  of  them  subsequently  perished  from 
hunger  or  frost.     In  addition  to  this  during  the  late  summer  of 


294      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

1894  there  was  an  excessive  drouth,  so  that  but  few  of  the 
second  brood  matured.  Thus  in  1895  there  were  very  few  of 
the  insects  to  be  seen. 

Among  the  birds,  the  common  crow,  the  red-breasted  gros- 
beak, and  turkeys  often  feed  upon  this  pest  to  a  considerable 
extent. 

Probably  the  most  destructive  insect-parasite  of  the  larvae  is  a 
Tachinid-fiy  known  to  science  as  Lydella  doryphorce  Ril.,  whi(;h 
rather  closely  resembles  the  common  house-fly,  both  in  size  and 
color.  A  single  egg  is  laid  on  a  potato-bug  and  from  it  hatches  a 
small,  footless  maggot  which  burrows  inside  the  bug.  When  the 
larva  enters  the  earth,  the  effect  of  the  maggot's  work  becomes 
apparent,  and  instead  of  transforming  to  a  pupa  and  beetle,  it 
shrivels  up  and  dies;  but  the  maggot  itself  contracts  into  a  hard, 
brown  pupa,  from  which  the  fly  eventually  emerges.  Thus  in 
1868,  when  first  noted  by  Dr.  C.  V.  Riley,  he  asserted  that  in 
Missouri  fully  10  per  cent  of  the  second  brood  and  one-half  of  the 
third  were  destroyed  by  this  parasite. 

Many  of  our  common  lady-bird  beetles  and  their  larvae  check 
the  pest  by  feeding  upon  the  eggs.  Several  predaceous  bugs,  par- 
ticularly the  spined  soldier-bug  (Podisus  spinosus  Dall.)  (Fig.  213) 

are  of  value  in  destroying  the 
larvae,    into  which   they   thrust 
their  short,  powerful  beaks,   and 
then    suck  out  the  juices  of  the 
body,    leaving    an  empty  skin. 
One   or   two  of  these  closely  re- 
semble the  common   squash-bug 
{Anasa  tristis  De  G.),    but    are 
really  very  dissimilar,  and  whereas 
Fig.  214.— Tachinid  parasite  of  Col-     the   beaks     of    the     predaceous 
orado     potato-beetle      (Lydella      forms  are  short  and  thick,  as  in 
donjphorce  Ril).   (After  Riley.)  -n-      mo  ^i  r     i      ^r      i 

•^^  Fig.  213,  a,  those,  of  plant-feed- 

ers, like  the  squash-bug,  are  long  and  slender,  as  in  Fig.  213,  6. 

Several  species  of  ground-beetles  are  often  found  preying  upon 
the  larvae  and  beetles,  but,  unlike  the  bugs,  attack  them  by  means 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES 


295 


of  their  powerful  biting  jaws.  These  beetles  are  also  exceedingly 
beneficial  in  feeding  upon  many  other  injurious  insects,  and  are 
among  the  farmers'  best  insect  friends  (Fig.  215). 

Remedies. — As  an  artificial  remedy  for  this  pest,  Paris  green 
has  long  been  proven  to  be  both  effectual  and  practical.  For 
small  areas  it  may  be  used  dry  by  mixing  it  with  fifty  times 
its  weight  of  dry  flour,  land-plaster,  or  air-slaked  lime,  and  should 
be  applied  while  the  plants  are  still  wet  with  dew,  either  by  a 
perforated  can,  or,  better,  by  one  of  the  improved  powder-guns 
such  as  Leggett's,  by  which  two  rows  of  plants  may  be  powdered 
at  once.  On  larger  areas  spraying  will    be    found  more  satisfac- 


FiG.  215. — Murky  ground-beetle  (i/arpaZas  ca%iftos«s);  a,  its  larva;  h,  head 
of  larva  showing  mouthparts.     (After  Riley.) 


tory.  One  pound  of  Paris  green  and  1  pound  of  freshly  slaked 
quicklime  to  50  gallons  of  water  will  kill  all  the  larvse,  but 
often  2  to  3  pounds  are  necessary  to  destroy  the  beetles. 

Many  growers  now  prefer  to  use  arsenate  of  lead  at  from  3  to  5 
pounds  to  the  barrel,  as  there  is  no  danger  of  burning  the  foliage 
with  it,  and  it  is  much  more  adhesive.  Where  Bordeaux  mixture 
is  not  used  the  arsenate  of  lead  is  much  preferable  on  account  of  its 
superior  adhesiveness.  Where  Bordeaux  mixture  is  used,  arsenite 
of  lime,  or  arsenite  of  lime  made  with  soda,  may  be  used,  but  these 
homemade  arsenicals  should  not  be  used  alone,  on  account  of 
their  burning  the  foliage. 

The  vines  should  be  sprayed  first  when  they  are  a  few  inches 
high,  and  the  spraying  repeated  once  or  twice  at  intervals  of  ten 


296    INSECT   PESTS   OF  FARM,  GARDEN    AND   ORCHARD 

days  or  two  weeks.  The  larvcc  are  so  easily  killed  by  arsenicals 
that  potato  growers  no  longer  fear  their  work,  but  large  quantities 
of  Paris  green  are  wasted  by  careless  application,  and  by  dusting 
unduly  large  amounts  wnth  poor  apparatus,  which  not  infrequently 
results  in  burning  the  foHage.  For  small  areas  a  bucket  or  knap- 
sack pump  will  be  found  satisfactory,  but  for  over  an  acre  a  barrel 
pump  with  a  row  attachment  will  prove  more  economical,  and  for 
over  ten  acres  a  geared  machine  spraying  several  rows  at  once  will 
be  needed.     Cleaning  up  the  vines  and  plowing  potato  land  in  the 


Fig.  216. — The   convergent   ladybird   {Hippodamia   convergens):  a,  Sidn\t;b, 
pupa;  c,  larva;  enlarged.     (After  Chittenden  U.  S.  Dept.  Agr.) 

fall  after  the  crop  has  been  harvested  will  aid  in  reducing  the  num- 
bers of  the  hibernating  beetles. 


Flea-beetles  * 

While  the  potatoes  and  tomatoes  are  but  a  few  inches  high  they 
are  often  attacked  by  myriads  of  small  black  beetles,  which  from 
their  power  of  making  long  quick  jumps  are  known  as  flea-beetles. 
They  soon  riddle  the  foliage,  often  so  badly  that  the  plants  wilt,  and 
replanting  is  necessary,  particularly  with  tomatoes. 

Several  species  are  known  to  attack  the  potato,  the  two  most 
common  being  the  potato  or  cucumber  flea-beetle  {Epitrix  cucum- 
eris  Harris)  and  one  which  Professor  H.  A.  Garman  has  styled  the 
Southern  Potato  Flea-beetle  {Epitrix  fuscula) .     The  Tobacco  Flea^ 

*  Family  ChrysomeUdoe. 


Fig.  217. — Field  sprayer,  witli  modifications,  adapted  for  potato  sjiraying, 
hy  L.  C'.  Corhctt,  operating  at  the  Virginia  Truck  Experiment  Station, 
Norfolk,  Va. 

297 


298      INSECT  PESTS   OF   FARM,    GARDEN  AND  ORCHARD 

beetle  {Epitrix  parvula)  is  not  uncommonly  found  on  the  vines  in 
sections  where  tobacco  is  also  grown,  and  other  species  do  similar 
injury  in  other  sections.  All  of  these  species  are,  however,  essen- 
tially the  same  in  habits  and  life  history,  and  the  same  remedies 
apply  to  all.  Unfortunately,  the  complete  life  cycle  of  these  little 
insects  has  never  been  carefully  determined,  so  that  only  a  general 
outline  can  l^e  given. 

The  potato  flea-beetle  *  is  the  most  destructive.  It  is  only 
one-sixteenth  inch  long,  jet  black,  except  the  yellowish  aniennse 
and  legs,  and  there  is  a  deep  groove  across  the  base  of  the  thorax 


Fig.  218.— a,  potato  flea-beetle;    b,  egg-plant  flea-beetle,  both  greatly 
enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

(Fig.  218,  a).  It  seems  to  occur  throughout  the  United  States, 
but  is  more  commonly  injurious  in  the  North.  Eggplant  and 
tobacco,  as  well  as  numerous  garden  vegetaljlcs  are  similarly 
injured.  This  species  has  commonly  been  called  the  cucumber  fiea- 
beetle  from  its  specific  name,  but  it  is  evidently  a  misnomer,  as  it 
is  much  more  abundant  upon  the  potato  and  related  plants. 

During  the  winter  the  beetles  hibernate  under  leaves,  rubbish, 
etc.,  and  in  the  spring  come  forth  and  lay  their  eggs  upon  the 
roots  of  some  of  our  common  weeds  of  the  Nightshade  family, 
such  as  the  horse-nettle,  Jamestown-weed,  Desmodium,  etc., 
in  May  and  June.  The  larvae  mine  in  the  roots  of  these  plants 
and  transform  to  pupse  in  small  earthen  cells  among  the  roots, 
*  Epitrix  cucumeris  Harris. 


INSECTS  INJURIOUS  TO  POTATOES  AND  TOMATOES       299 

from  which  the  beetles  come  forth  to  attack  the  fohage  of  the 
crops  mentioned.  There  are  at  least  two  and  probably  three 
generations  a  year,  but  the  life  history  of  the  species  has  not  l:)een 
carefully  studied.  The  larva?  are  minute,  thread-like,  white 
worms. 

Occasionally  the  larva^  mine  into  the  tubers,  doing  considerable 
damage  and  causing  "  pimply "  potatoes.  Such  injury  was 
quite  common  in  New  York,  in  1894,  and  in  Colorado  in  1903. 

The  principal  injury  by  the  beetles  is  done  to  the  young  foliage 
just  after  it  is  up  in  the  spring,  when  then  swarm  upon  the  plants 
and  thoroughh'  riddle  the  leaves,  a  badly  eaten  leaf  appearing 
as  if  it  had  been  hit  by  a  charge  of  fine  bird-shot.  The  complete 
life  history  of  the  species  has  not  been  definitely  determined, 
but  the  injury  by  the  adults  is  rarely  troublesome  except  when 
the  plants  are  young,  and  the  larval  injury  to  the  tubers  occurs 
later  in  the  season. 

The  Eggplant  Flea-beetle  *  so  nearly  resembles  the  previous 
species  that  it  will  not  be  distinguished  from  it  but  l3y  the  entomol- 
ogist. It  is  slightly  larger,  however,  with  the  wing-covers  more 
hairy,  and  the  groove  at  the  base  of  the  thorax  is  not  so  distinct. 
It  has  much  the  same  food-plants,  but  is  particularly  abundant 
on  eggplant,  and  is  more  commonly  injurious  in  the  South,  below 
the  Ohio  and  Potomac  rivers. 

The  Tobacco  Flea-beetle  f  has  been  previously  discussed 
(page  222),  but  should  be  mentioned,  as  it  is  commonly  injurious 
to  potato,  tomato,  and  eggplant  throughout  the  South,  as  well 
as  to  tobacco,  and  occasionally  to  corn  and  other  plants. 

Control. — It  has  been  found  that  Bordeaux  mixture  acts  as 
an  excellent  repellant  against  these  little  beetles,  and  that  plants 
well  covered  with  it  are  not  seriously  injured.  Inasmuch  as 
it  is  always  advisable  to  spray  potatoes  as  soon  as  they  are  a 
few  inches  high  for  fungous  diseases  and  for  the  Colorado  potato 
beetle,  by  applying  the  spray  as  soon  as  possible  after  the  plants 
are  up  they  will  be  protected.  Both  potatoes  and  tomatoes 
should  be  sprayed  with  Bordeaux  mixture  and  arsenate  of  lead 
*  Epitrix  fuscula  Cr.  f  Epitrix  parvula  Fab. 


300        INSECT  PESTS  OF   FARM,  GARDEN  AND   ORCHARD 

or  Paris  green  as  soon  as  they  are  a  few  inches  high.  The  spray 
should  be  apphed  hbcrally  so  as  to  give  the  plants  a  distinct 
coating  of  the  mixture.  Tomatoes  are  particularly  susceptible 
to  injury  and  might  be  dipped  in  arsenate  of  lead  when  planting, 
using  1  pound  to  10  gallons  of  water.  The  destruction  of  the 
weeds  upon  which  the  larvse  commonly  develop  is  obviously 
important  in  preventing  their  multiplication. 

Where  injury  by  the  larva?  is  done  to  the  tubers,  it  is  recom- 
mended that  they  be  dug  as  soon  as  possible,  and  be  left 
exposed  to  the  sun  for  a  few  hours  after  digging  so  as  to  harden  the 
skin,  before  being  stored.  If  damage  continu(\s  in  storage,  the 
tubers  may  be  fumigated  with  carbon  bisulfide,  as  recommended 
for  grain  insects  (page  57) . 

Potato-scab  and  Insects 

That  certain  forms  of  what  is  commonly  termed  "  potato- 
scab  "  are  due  to  the  work  of  insects  has  frequently  been  shown. 
In  1895  Professor  A.D.  Hopkins,*  of  the  West  Virginia  Agricultural 
Experiment  Station,  reported  some  very  careful  original  investiga- 
tions upon  two  species  of  gnats,  Epidapus  scabies  Hopk.  and  Sciara 
sp.,  the  larvse  of  which  had  been  conclusively  shown  to  cause 
a  "  scab  "  upon  the  tubers  by  boring  into  them.  The  larvae 
or  maggots  of  the  Potato-scab  Gnat  are  about  one-sixth  of  an 
inch  long,  and  are  the  young  of  a  wingless  gnat  shown,  very 
great'y  enlarged,  in  Fig  219.  The  females  deposit  their  eggs  on 
the  potatoes  in  storage  frorn  autumn  to  spiing,  and  the  maggots 
hatching  from  them  enter  old  scab  spots  or  injured  places.  Under 
favorable  conditions  a  generation  may  be  developed  in  twenty 
to  twenty-five  days.  Later  in  the  spring  the  eggs  are  deposited 
in  manure  or  other  decomposing  material,  on  seed  potatoes  or 
pn  growing  tubers  to  which  they  may  be  carried  on  seed  potatoes. 
When  they  become  well  established  in  a  potato,  it  is  soon  des- 
troyed if  they  are  not  overcome  b}'  their  natural  enemies,  or 
unless   the   soil   becomes  dry,    when   they  soon   disappear.      In- 

*  A.  D.  Hopkins,  Special  Bulletin  2  (\'o].  IV,  No.  3)  AV.  Va.  Agr.  Exp. 
Sta.,  p.  97. 


INSECTS   INJURIOUS   TO  POTATOES  AND  TOMATOES       301 

fcsted  places  look  very  much  like  the  ordinary  scab  produced 
b}'  the  scab  fungus  and  may  l)e  readily  mistaken  for  it.  Such 
injur}'  was  c^uite  general  and  serious  in  West  \'irginia  in  1S91  and 
1S92.  Dr.  Hopkins  found  that  "  they  breed  in  and  are  especially 
common  in  Inirnyard-manure,"  that  ''  excessive  moisture  in  the 
soil  has  been  ol)served  to  be  the  most  favorable  condition  for 
their  tlevelopment,"  and  that  "  soaking  the  seed-potatoes  in  a 
solution  of  corrosive  sublimate  previous  to  planting  "  will  kill  all 
the  eggs  and  young  larva^,  as  it  will  also  destroy  the  spores  of 
the  potato-scab  fungus. 

Professor  H.  Garman  *  has  also  recorded  the  injuries  of  several 
species    of    millipedes,    or    "  thousand-legged    worms,"    Camhala 


Fig.  219. — Potato  scab-gnat  {Epidapus  scahei  Hopk.):    a,  fly;    i,  larva;    g 
egg;  h,  egg  mass — much  enlarged.     (After  Hopkins.) 

annidata  and  Parajulm^  impressus,  as  causing  a  scab  by  gnawing 
into  the  surface  of  the  tul)ei's.  Though  both  of  these  observations 
are  unciuestionably  true,  such  injury  has  not  occiu'red  [n  other 
parts  of  the  country,  and  it  is  improl3al)lc  that  an}'  large  portion 
of  potato-scab  is  due  to  these  insects.  Potato-scab  is  a  fungous 
disease,  which,  as  already  noted,  may  be  destroyed  by  soaking 
the  seed-potatoes  in  a  solution  of  corrosive  sublimate. 


Blister-beetles  f 

Long  before  we  had  made  the  acquaintance  of  the  Colorado 
potato-])eetle,  several  species  of  blister-beetles  frequently  brought 

*  H.  Garman,  Bulletin  61,  Ky.  Agr.  Exp.  Sta.,  p.  18. 
f  Family  Meloiduc. 


302      INSECT  PESTS  OP  FARM,  GARDEN  AND  ORCHARD 

themselves  into  notice  by  their  injuries,  and,  therefore  are  now 
known  as  the  "  old-fashioned  potato-bugs."  The  name  of 
"  blister-beetles  "  has  been  bestowed  upon  them  because  of  the 
blistering  effect  which  they  have  upon  the  skin,  they  being  nearly 
related  to  the  Spanish  fly,  used  for  that  purpose. 

One  of  the  most  common  of  these  is  the  Striped  Blister-beetle, 
which  has  three  yellow  stripes  upon  its  wing-covers,  while 
two  other  common  forms  are  of  a  slate-black  color.  Very  often 
when  these  beetles  congregate  in  numbers  they  are  a  great 
nuisance,  not  only  in  the  potato-patch,  but  upon  many  other 
plants  of  the  garden  or  truck-farm. 

Unfortunately,  they  present  to  the  farmer  a  very  peculiar 
problem,  for  while  the  beetles  are  often  exceedingly  injurious, 
the  larvae  are  even  more  beneficial,  in  eating  large  quantities  of 
grasshoppers'  eggs. 

Life  History. — The  life  of  these  insects  is  unique.  The  female 
lays  a  large  number  of  eggs  in  a  small  cavity  in  the  earth,  and 
from  these  hatch  some  small,  long-legged  larvse,  which  run  about 
searching  for  the  pod-like  masses  of  grasshoppers'  eggs,  upon 
which  they  feed.  As  soon  as  the  appetite  of  one  of  these  little 
egg-hunters  is  appeased,  he  sheds  his  skin,  and  now  being  sur- 
rounded by  food  and  no  longer  needing  his  long  legs  for  running, 
in  the  next  stage  of  his  existence  his  legs  become  very  short  and 
rudimentary,  and  he  remains  almost  immobile  while  feeding  upon 
the  rest  of  the  eggs. 

Control. — Spraying  with  Paris  green  or  arsenate  of  lead,  as 
advised  for  the  Colorado  potato-beetle  will  kill  the  beetles,  and 
where  the  vines  have  been  regularly  sprayed  but  little  trouble 
will  be  had  with  them.  Where  they  suddenly  appear  in  large 
-swarms  in  gardens  or  on  truck  land,  they  are  often  destroyed  by 
a  line  of  men  and  children  slowly  driving  them  with  branches,  as 
the  beetles  move  but  slowly.  If  a  ditch  is  available  it  may  be 
oiled,  and  the  beetles  destroyed  like  grasshoppers  (page  108),  or 
they  may  be  driven  into  a  windrow  of  straw,  hay,  or  any  inflam- 
mable rubbish  and  burned  in  it. 


INSECTS   INJURIOUS   TO  POTATOES   AND  TOMATOES        303 

Three-lined  Leaf -bee  tie  * 

Closely  related  to  the  Colorado  potato-beetle,  and  very 
similar  to  it  in  habits,  is  the  Three-lined  Leaf-beetle.  The  eggs 
may  be  distinguished  by  the  fact  that  they  are  usually  laid  in 
rows  along  the  midrib  on  the  under  side  of  the  leaf,  while  those 
of  the  potato-beetle  are  laid  indiscriminately  in  bunches.  The 
larvie,  however,  may  be  readily  distinguished  from  all  other 
insects  attacking  the  potato  by  being  covered  with  a  disgusting 
mass  of  their  own  excrement. 


Fig.  220. — Three-lined  leaf-beetle  (Lenia  trilineata  Oliv.);     a,  larva;  b,  pupa; 
d,  eggs;  beetle  at  right.     (After  Riley.) 


There  are  two  l)roods  during  the  season,  the  larvse  of  the  first 
appearing  in  June,  and  that  of  the  second  in  August;  but  the 
beetles  of  the  second  brood  do  not  emerge  until  the  following 
spring.  In  other  respects  the  life  history  is  practically  the  same 
as  that  of  the  Colorado  potato-beetle.  The  beetle  is  of  a  pale 
yellow  color,  with  three  black  stripes  on  its  back,  and  in  a  general 
way  resembles  the  common  striped  cucumber-beetle  (Diabrotica 
rittata  Fal).),  though  it  is  somewhat  larger  and  the  thorax  is 
decidedly  constricted. 

In  case  it  becomes  necessary  to  destroy  the  blister-beetles,  both 
they  and  the  three-lined  leaf-beetle  may  be  readily  disposed  of  by 
applying  Paris  green  or  other  arsenite  as  advised  for  the  Colorado 
potato-beetle. 

*  Lema  trilineata  Oliv.     Family  Chrysomelidce. 


304        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Tomato  Worms 

The  largo  gi'cen  horn-worms  whicli  attack  the  foliage  of  the 
tomato  are  the  same  as  those  previously  described  which  attack 
tobacco  (see  page  22S).  Usually  they  are  not  so  numerous  but 
that  they  may  be  readily  controlled  by  handpicking,  but  if  neces- 
sary the  same  remedial  measures  may  used  as  advised  for  them  on 
tobacco. 

The  Tomato  Fruitworm 

The  worms  which  commonly  ])ore  into  the  green  and  ripening 
tomatoes  are  the  same  as  the  tobacco  l>udworm  and  the  cotton 
bollworm  (see  pages  234  and  254),  under  which  names  their  habits 
and  life  histories  have  l^een  fully  described. 

(Obviously  tomatoes  should  not  be  planted  on  land  which  has 
been  in  corn  or  cotton  infested  by  this  insect  the  previous  year, 
unless  it  has  been  given  thorough  winter  plowing  and  harrowing. 

It  has  seemed  to  the  writer  that  trap  rows  of  sweet  corn  might 
be  used  for  protecting  tomatoes  as  they  are  used  with  cotton,  but 
no  experiments  seem  to, have  been  conducted  which  show  the  prac- 
ticability of  the  method.  As  the  young  caterpillars  feed  a  little  on 
the  foliage  before  Ijoring  into  the  fruit,  a  thorough  spraying  with 
arsenate  of  lead,  3  pounds  to  50  gallons,  will  undoubtedly  protect 
the  tomatoes  if  applied  as  soon  as  the  eggs  are  laid,  and  with  one 
or  two  later  applications  at  intervals  of  ten  days,  the  exact  time 
depending  upon  the  latitude  and  season,  as  indicated  by  the  life 
history  (seepage  181). 


CHAPTER  XVI 

INSECTS  INJURIOUS  TO  BEANS  AND  PEAS  * 

The  Pea-weevil  f 

The  common  Pea-\veevii  occurs  in  almost  all  parts  of  the  world 
where  peas  are  grown,  and  is  the  usual  cause  of  "  buggy  "  peas.  It 
was  the  cause  of  the  abandonment  of  pea  growing  in  the  central 
Atlantic  States  as  early  as  the  middle  of  the  eighteenth  century. 
It  has  usually  been  regarded  as  a  native  of  North  America,  having 


Fig.  221. — The  j^oa-weevil  {Bruchuf-  pisorum  L.):   a,  adult  beetle;    h,  larva; 
c,  pupa — all  enlarged.     (From  Chittenden,  U.  S.  Dept.  Agr.) 

been  introduced  into  Europe.  It  does  but  comparatively  little 
damage  in  more  northern  latitudes  and  for  this  reason  seedsmen 
secure  their  seed  peas  from  Canada  and  northern  Michigan  and 
Wisconsin. 

The  weevil  is  about  one-fifth  inch  long  and  about  one-half 
that  width,  being  the  largest  of  the  pea-  and  bean-feeding  weevils 
in  this  country.  "  Its  ground  color  is  black,  but  it  is  thickl}^  cov- 
ered with  brown  pubescence,   variegated  with  black  and  white 

*  See  F.  H.  Chittenden,  Insects  Injurious  to  Beans  and  Peas,  Yearljook 
U.  S.  Dept.  Agr.  for  1S9S,  p.  233. 

t  Bruchus  pisorum  Linn.     Family  Br-uchidce. 

305 


306      INSECT  PESTS    OF  FARM,    GARDEN  AND  ORCHARD 


markings  as  shown  in  Fig.  221.  The  sides  of  the  thorax  are  notched 
or  toothed,  and  the  abdomen,  which  projects  beyond  the  wing- 
covers,  is  coated  with  whitish  pubescence  and  marked  by  two  black 
spots.  The  hind  thighs  are  thickened  and  each  bears  two  promi- 
nent teeth." 

Life  History. — The  winter  is  passed  in  the  adult  stage,  the  wee- 
vils making  their  appear- 
ance in  the  fields  when  the 
peas  are  in  blossom.  The 
eggs  are  laid  singly  upon 
the  surface  of  the  pods, 
attached  by  a  sticky  fluid 
which  becomes  white  when 
dry.  The  egg  is  about  one- 
twentieth  of  an  inch  long 
by  one-third  that  width,  of 
a  yellow  color,  as  shovra  in 
Fig.  222. 

Fig.  222.— The  pea-weevil:  a,  egg  on  pod;         Upon       hatching,       the 

fe,  cross-section  of  opening  of  larval  mine;  ,  i  ,i  i 

'  ,  1  •  ■    -A      (  voung  larva   bores  through 

c,  young  larva  and  opening  on  mside  of  -  t?  & 

pod  by  which  it  has  entered — enlarged    the  pod  and  into  the   seed. 

d  d,  d    eggs  on  pod,  slightly  enlarged;  j^^  ^j^-g  ^^         ^j^^  \^^^^  ^^^ 

J,  leg   of  larva;    g,   prothoracic  spurious  ° 

processes— more  enlarged.     (After  Chit-  some  very  small   false   legs 

tenden,  U.  S.  Dept  Agr.)  ^nd    two    plates    and    six 

strong  spines  on  the  thorax,  which  aid  it  in  getting  through  the 

pod.     Upon  entering  the  seed  the  skin  is  shed  and  these  legs, 

plates    and   spines   are   lost.     The   larva   feeds   upon   the  seed, 

growing  rapidly.     When  full  grown  it  appears  as  at  h,  Fig.  221. 

It    resembles    a  maggot    in    general    appearance,  being  white, 

except  the  small  mouth-parts,  which  are  brown;  is  fleshy,  nearly 

cylindrical    and    strongly   wrinkled,    with    three   pairs    of    very 

short  stubby  legs.     It  is  about  one-fourth  an  inch  long  and  half 

as  broad.     Before  its  final  molt  the  larva  eats  a  round  hole  in  the 

pea,  leaving  but  a  thin  membrane  as  a  covering.     It  then  lines  the 

inside  of  the  pea  with  a  glue-like  substance,  and  within  this  cell 

transforms  to  the  pupa. 


I 


INSECTS  INJURIOUS  TO  BEANS  AND   PEAS  307 

The  pupa  is  white,  showing  the  notches  at  the  sides  of  the 
thorax,  but  otherwise  is  not  dissimilar  from  many  weevil  pupa. 
The  length  of  the  pupal  stage  varies  from  nine  to  seventeen  or 
more  days.  In  more  southern  latitudes  a  large  part  of  the  beetles 
leave  the  seed  in  August,  but  in  the  North  they  all  remain  in  the 
seed  over  winter,  and  are  planted  with  the  seed.  There  is  but  one 
generation  a  year  and  this  species  does  not  breed  in  dry  peas. 

Injury. — Dr.  James  Fletcher  has  stated  that  this  pest  is  now 
doing  over  $1,000,000  damage  in  Ontario  alone  annuall}^,  and  that 
the  growing  of  peas  has  been  abandoned  in  considerable  areas  of 
that  province.  In  large  peas  about  one-sixth  of  the  food  content 
is  destroyed,  while  in  smaller  varieties  fully  one-half.  Not  only 
this,  but  in  eating  canned  green  peas  one  frequently  devours  sev- 
eral small  larva^  in  each  mouthful,  unawares,  as  but  a  small  dark 
speck  indicates  their  presence  in  the  green  pea.  In  the  dry  seed 
the  holes  made  by  the  larvae  can  be  seen.  But  12  to  18  per  cent  of 
infested  seed  will  produce  plants,  which  are  later  in  developing  and 
do  not  yield  as  well  as  those  unaffected. 

Enemies. — The  Baltimore  oriole  has  been  recorded  as  feeding 
on  the  grubs  by  splitting  open  the  pods,  and  the  crow  l^lackbird  is 
said  to  devour  many  of  the  beetles  in  the  spring-.  Practically  no 
parasites  or  predaceous  insects  are  known  to  pre}'  upon  it,  so  that 
it  has  every  opportunity  for  doing  serious  injury. 

Control. — Holding  over  Seed. — One  of  the  best  means  of 
destroying  the  weevils  where  ]3ut  a  few  peas  are  concerned  and  cir- 
cumstances will  permit,  is  to  simph'  hold  them  over  for  a  season, 
stored  in  a  tight  sack  or  box,  before  planting.  As  the  weevils  will 
not  breed  in  the  dried  peas  they  die  in  the  sack  and  are  thus  caught. 
Peas  should  always  be  l^agged  up  and  sacks  tied  immediately  after 
threshing. 

Late  Planting. — Comparative  immunity  from  injury  is  claimed 
by  some  growers  for  late-planted  peas.  Dr.  F.  H.  Chittenden  is 
inclined  to  the  belief  that  in  some  localities,  such  as  Washington, 
D.C.,  where  two  crops  can  be  grown  in  a  3'ear,  that  late  planting  is 
all  necessary  to  secure  sound  seed  stock. 

Treating  with   Kerosene. — The   Canadians   have  foiuid   that 


308       INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 

kerosene  may  be  used  to  destroy  the  weevils.  Dr.  Fletcher  states : 
"A  remedy  which  has  been  used  by  many  farmers  with  satisfaction 
is  to  drench  the  seed  with  coal  oil,  using  about  a  half  a  gallon  to  the 
barrel,  or  five  bushels  of  peas.  While  applying  the  coal  oil  (kero- 
sene) the  seed  should  be  placed  on  the  floor,  where  it  can  be  shoveled 
over  constantly  to  insure  the  treatment  of  all  the  grain." 

Scalding  Seed. — "  When  peas  are  found  to  contain  live  weevils 
at  the  time  of  sowing,  these  may  be  destroyed  by  simply  pouring 
them  into  a  pot  of  scalding  water.  The  water  should  be  drained 
off  at  once  or  the  seed  cooled  by  turning  in  cold  water," — Fletcher. 

Heat. — Dr.  Chittenden  states  that  it  has  been  found  that  a  tem- 
perature of  145°  F.  will  kill  the  weevils  in  the  seed  without  injury 
to  the  germinating  property  of  the  seed. 

Fumigation. — This  is  undoubtedly  the  best  means  of  destroy- 
ing the  weevils,  and  is  now  coming  into  general  use.  Dr.  Fletcher, 
who  has  made  the  most  thorough  studies  of  practical  methods  for 
controlling  this  pest,  states :  "  Fumigation  with  bisulfide  of  car- 
bon is  a  sure  remedy.  When  properly  done,  either  in  specially 
constructed  buildings  known  as  '  bug-houses  '  or  in  any  tight  bin, 
every  weevil  is  surely  killed  if  the  seed  containing  them  is  fumi- 
gated for  forty-eight  hours  with  this  chemical,  using  1  pound  by 
weight  to  every  100  bushels  of  seed,  or,  in  smaller  quan  ities,  1 
ounce  to  every  100  pounds.  For  the  treatment  of  small  quantities 
of  seed,  particularly  by  farmers,  I  have  found  that  an  ordinary 
coal-oil  barrel  is  very  convenient.  This  will  hold  about  5  bushels, 
or  300  pounds  of  seed,  which  may  be  treated  with  3  ounces  of  bisul- 
fide of  carbon.  Care  must  be  taken  to  close  up  the  top  tightly. 
This  is  best  done  with  a  cap  made  specially  for  the  purpose,  but 
fine  sacks  laid  smoothly  on  the  top,  over  which  boards  are  placed 
with  a  weight  on  them,  will  answer.  Fumigation  with  bisulfide 
of  carbon  is,  I  believe,  the  remedy  most  to  be  relied  upon  in  this 
campaign.  It  is  perfectly  effective,  is  now  regularly  used  by  the 
large  seed  merchants,  and  in  future  will  be  much  more  generally 
used." 

(For  directions  for  use  of  bisulfide  of  carbon  and  caution 
concerning  it,  see  page  57.) 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


309 


The  Common  Bean-weevil  * 

Throughout  the  United  States  the  common  Bean-weevil  is  the 
principal  enemy  of  the  bean.  The  small,  white,  footless  grubs 
feed  within  the  beans,  both  in  the  field  and  in  storage,  and  trans- 
form to  the  common  brown-gray  weevils  which  infest  white  beans. 
In  the  South  its  attacks  are  so  serious  that  it  is  almost  impossible 
to  secure  a  crop  uninfested,  so  that  most  of  the  beans  both  for 
seed  and  consumption  come  from  the  North.  Not  until  1870  did 
injury  by  this  insect  attract  attention  in  the  United  States,  but 
now  it  occurs  throughout  our  borders  and  is  practically  cosmopol- 


FiG.  223. — The  common  bean-weevil  {Bruchus  obtectus  Say):    a,  beetle;    b, 
larva;  c,  pupa — all  greatly  enlarged.     (After  Chittenden,  U.  S.  D.  Agr.) 


itan  in  its  distribution.  It  is  probably  a  native  of  Central  or 
South  America. 

The  adult  weevil  is  about  one-eighth  of  an  inch  long  and  is  cov- 
ered with  a  fine  brown-gray  or  olive  pubescence,  giving  it  that 
color,  while  the  wing-covers  are  mottled  as  shown  in  Fig.  223,  a.  It 
may  be  distinguished  from  the  pea- weevil  by  its  longer  thorax  and 
by  the  two  small  teeth  next  to  the  large  tooth  at  the  tip  of  the 
thighs. 

Life  History. — In  the  field  the  eggs  aiv  laid  upon  or  are  inserted 
in  the  bean-pod  through  holes  made  by  the  female  or  such  open- 

*  Bruchus  obtectus  Say.     Family  Bruchidoe. 


310      INSECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 

ings  as  are  caused  by  its  drying  and  splitting  (Fig.  224,  b,  c) .  In 
shelled  beans  the  eggs  are  placed  loosely  among  them  or  in  the 
exit  holes  of  the  beetles.  The  young  larva  hatching  from  the  egg 
has  long,  slender  legs,  but  with  the  first  molt  these  are  lost  and 
when  full  grown  it  is  a  fat  grul3  as  shown  in  Fig.  223,  b.  The  pupal 
stage  is  passed  in  an  oval  cell  made  by  the  larva  within  the  bean. 
Experiments  have  shown  that  the  eggs  hatch  in  from  five  days  in 
the  hottest  to  twenty  days  in  cooler  weather;  the  larval  stage 
requires  eleven  to  forty-two  daj's,  and  the  pupal  stage  five  to  eigh- 


FiG.  224. — The  bean-weevH;  a,  .side  view  of  beetle;  b,  section  of  bean  pod 
showing  sHt  for  deposition  of  egg;  c,  part  of  inside  of  pod  showing  egg- 
mass  inserted  through  slit — all  enlarged.  (After  Riley  and  Chittenden, 
U.  S.  Dept.  Agr.) 

teen  days.  Thus  the  whole  life  cycle  will  extend  over  a  period  of 
from  twenty-one  to  eighty  clays,  depending  upon  the  season  and 
locality.  Probably  a'  out  six  generations  occur  annually  in  the 
District  of  Columbia,  and  a  less  number  further  north. 

"  Unlike  the  pea- weevil,  a  large  number  of  individuals  w^ill 
develop  in  a  bean,  as  many  as  twenty-eight  having  beenf  ound 
within  a  single  seed.  It  will  thus  be'readily  seen  that  the  first  out- 
door generation  or  any  single  indoor  generation  is  capable  of 
exhausting  seed  and  completely  ruining  it  for  food  or  planting  or 
any  other  practical  purpose,  except  perhaps  as  hog  feed." 

"  The  beetles  begin  to  issue  from  beans  in  the  field  in  a  climate 


INSECTS  INJURIOUS  TO   BEANS   AND   PEAS 


311 


like  that  of  the  District  of  Cokimbia  ...  as  early  as  October, 
when  in  the  natural  course  of  events  the  eggs  for  a  new  brood 
would  be  deposited  in  such  pods  as  had  cracked  open,  so  as  to 
expose  the  seeds  within." 

"  Weevilly  "  seed  should  never  be  planted,  as  but  a  small  per 
cent  of  it  will  germinate  and  the  vitalit}'  of  that  germinating  is 
deficient.  Professor  Popenoe  showed  in  experiments  at  Manhattan, 
Kan.,  that  only  50  per  cent  of  the  infested  seed  used  germinated, 
that  only  30  per  cent  could  ha  e  grown  further,  and  that  even 
these  would  have  produced  plants  of  little  vigor  or  productive- 
ness.    (Quotations  and    acts  from  Chittenden,  I.e.) 

Remedies. — No  methods  are  known  of  preventing  injury  in  the 
field,  and  all  remedial  measures  must  be  applied  to  the  insects  in 
the  stored  seed.  As  this  pecies  breeds  in  the  stored  seed,  it  is  use- 
less to  hold  it  over  as  for  the  pea-weevil,  and  the  quicker  infested 
seed  is  treated  the  better.  Either  heat,  or  better,  fumigation,  as 
described  for  the  pea- weevil,  should  be  used.  When  ready  to  plant, 
seed  should  l)e  thrown  lightly  into  water,  when  that  l)adly  infested 
will  float  and  can  be  separated  and  destro}'ed. 


Other  Bean-weevils 

The  Coiv-pea  weevil* — This  species  may  l^e  readily  recognized 

by  the  two  large,    raised 

white  lobes  at  the  l^ase  of 

the  thorax  and  the  strongly 

pectinate  antenna;  of  the 

maleasshowninFig.  225,a.      y"^  MmBaM  V  i 

The  cow-pea  is  the  favorite 

food-plant  of  this  and  the 

following  species,  but  peas 

and  various  sorts  of  beans    Fig.  225. — The  cow-pea  weevil  (Bruchus  chi- 

are  also    attacked.      This       f ^"^^"^  ^"^ ;  «'  f""^^  "^fl  ^'^^^J , ''  ^^^'^^ 

larva;  a,  iront  view  of  head  of  'same;  e, 

species  is  a  southern  form,         thoracic  leg  of  same;— a,  much  enlarged; 

but  seems  to  he  spreading,         ^'  t'  "''^''^  enlarged.     (After  Chittenden, 

.  U.  S.  Dept.  Agr.) 

incident  to  the  more  wide- 


Bruclius  chinensi.s  L!nn 


312       INSECT  PESTS  OF  FARM,  GARDEN   AND  ORCHARD 

spread  growth  of  the  cow-pea.     Like  the  common  bean- weevil  it  is 
practically  cosmopolitan  in  its  diRtril)ution,  but  is  most  injurious 


Fig.  226. — The  four-spotted  bean-weovil :    a,  beetle;    h,  larva;    c,  pupa — all 
enlarged.     (After  Chittenden,  II.  S.  Dept.  Agr.) 

in  tropical  regions.     The  life  history  and  remedial  measures  are 
practically  the  same  as  for  the  common  bean-weevil. 

The  Four-Spotted  Bean-weevil* — The  wing-covers  of  this  species 


Fig.  227. — The  four-spotted  bean-weevil:  a,  cow-pea  showing  holes  made 
by  weevils  in  their  escape  from  seed,  also  eggs  deposited  on  surface;  h, 
egg;  c,  young  larva;  d,  head  of  same;  e,  prothoraeic  leg;  /,  spine  above 
spiracle  of  first  abdominal  segment — o,  twice  natural  size;  h,  f,  greatly 
enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

are  covered  with  gray  and  white  pubescence  and  four  darker  spots 
from  which  the  species  is  named.     It  is  more  slender  than  the  pre- 
ceding species  and  the  antennee  of  the  male  arc  not  pectinate. 
*  Bruchus  quadrimaculatu.s  Fab 


INSECTS   INJURIOUS  TO  BEANS  AND  PEAS  313 

The  markings  are  quite  variable,  but  the  most  common  form  is 
that  shown  in  Fig.  226.  This  is  an  exotic  species  occurring  from 
Mexico  to  Brazil  and  in  the  Mediterranean  countries.  In  1S85  it 
was  found  at  the  Atlanta  Cotton  Exposition  in  black-eyed  beans 
from  Texas,  and  has  since  become  acclimated  as  far  north  as  Iowa. 
It  seems  to  breed  more  readily  in  fresh  and  slightly  moist  seed  and, 
like  the  preceding  species,  its  work  in  stored  beans  seems  to  soon 
cause  decomposition  and  a  consequent  rise  of  temperature.  The 
life  history  and  remedial  measures  are  similar  to  those  of  the  bean- 
weevil. 

The  European  Bean-ireevil  *  was  imported  into  New  York  and 
New  Jersey  in  1870,  at  the  Columbian  Exposition  at  Chicago  in 
1893,  and  has  been  observed  at  College  Station,  Texas,  but  does 
not  seem  to  have  become  established  in  this  country.  It  closely 
resembles  the  pea-weevil  in  appearance  and  life  history. 

The  Bean  Leaf-beetle  t 

Small  yellowish  or  reddish  beetles,  marked  with  black,  as 
shown  in  Fig.  228,  and  from  one-seventh  to  one-fifth  inch 
long,  are  often  found  eating  the  foliage  of  beans,  and  are  commonly 
known  as  Bean  Leaf-beetles.  The  species  occurs  throughout  the 
United  States  east  of  the  Rockies,  but  has  been  chiefly  injurious 
in  the  Middle  and  Southern  States.  Besides  beans,  the  beetles 
feed  upon  cow-peas  and  various  native  plants  such  as  beggar- 
weed  or  tickseed,  tick  trefoil  (Meibomia),  bush-clover  (Lespedeza), 
and  hog-peanut  {Falcata).  They  usually  become  quite  numerous 
before  they  are  observed,  for  during  most  of  the  day  they  rest  or 
feed  on  the  under  sides  of  the  leaves.  They  are  sluggish  and 
seldom  fly,  and  when  disturbed  often  drop  to  the  ground,  though 
they  soon  crawl  back  to  the  plant.  Large  round  holes  are  eaten 
in  the  foliage  until  finally  nothing  but  the  veins  and  midrib  of  a 
leaf  is  left,  the  manner  of  defoliation  being  quite  characteristic 
of  this  species.  Low-growing  and  dwarf  varieties  are  worse  injured, 
as  pole  beans  put  out  new  leaves  after  the  injury  has  stopped. 

*  Bruchus  rufimanus  Boh. 

t  Ceratoma  trifurcata  Forst.     Family  ChrysomelidcB. 


314       INSECT  PESTS  OF  FARM,   GARDEN  AND   ORCHARD 

Life  History. — The  adult  beetles  hibernate  in  or  near  the  bean- 
fields  and  emerge  from  April  to  June  according  to  the  latitude. 
Minute  orange-colored  eggs  are  laid  near  the  stem  of  the  plant, 
just  below  the  surface  of  the  soil,  in  clusters  of  six  to  ten  or  more, 
and  hatch- in  from  five  to  eight  days.  The  young  larvae  feed  upon 
the  stem  and  roots,  becoming  full  grown  in  six  or  seven  weeks. 
When  grown  the  larva  is  about  three-tenths  an  inch  long, 
about  one-eighth  as  wide,  cylindrical,  milk-white  in  color,  with 
dark  head  and  anal  segment,  as  shown  enlarged  six  times  in  Fig. 


Fig.  228. — The  bean  leaf -beetle  {Ceraloma  irifurcata  Forst.):  a,  adult 
beetle;  h,  pupa;  c,  larva;  d,  side  view  anal  segment  of  larva;  e,  leg  of 
same;  /,  egg — a,  b,  c,  enlarged  about  six  times;  d,  e,  f,  more  enlarged. 
(After  Chittenden,  U.  S.  Dept.  Agr.) 

228.  The  pupa  (Fig.  228,  b)  is  pure  white,  and  from  it  the  beetle 
emerges  in  five  to  eight  days.  Thus,  in  the  District  of  Columbia,  the 
whole  life  cycle  requires  six  to  nine  weeks,  depending  upon  heat 
and  moisture.  In  the  North  there  is  probably  but  one  generation 
a  year;  in  Maryland  and  Virginia  one  generation  develops  in 
July  and  another  in  September;  while  in  the  Gulf  States  there 
are  probably  three  generations,  as  beetles  are  numerous  in  October. 
Remedies. — Spraying  with  arsenical  poisons  as  for  the  bean 
ladybird  (page  316)  is  the  most  effectual  means  of  controlling 
the  pest  when  abundant,  but  they  should  be  applied  early  to  avoid 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS 


;i5 


the  poison  on  l^eans  to  be  eaten  green. 
Owing  to  the  shiggishnes?  of  the  beetles 
they  may  be  handpicked  in  small  gar- 
dens. Clean  culture  and  careful  weed- 
ing of  native  food-plants  near  cultivated 
crops  such  as  tick-trefoil  and  bush- 
clover,  are  most  important. 

The  Bean  Ladybird  * 

The  Bean  Ladybird  is  the  most 
serious  enemy  of  beans  in  Colorado, 
New  Mexico,  Arizona,  and  Western 
Kansas,  whence  it  migrated  from 
Mexico.  It  is  an  interesting  insect  in 
that  only  two  other  native  species  of 
this  family  of  beetles  iCoccinellidoe)  feed 
upon  vegetation,  the  normal  food  of  the 
family  being  plant-lice,  scale  insects, 
and  soft-bodied  larvse. 

Professor  C.  P.  Gillette  f  describes 
it  as  follows: 

"  The  beetle  (Fig.  229,  A)  is  oval  in 
outline,  nearly  one-third  an  inch  in 
length  by  one-fifth  an  inch  in  l^readth, 
of  a  light  yellow  to  a  yellowish-brown 
color  and  has  eight  small  black  spots  on 
each  wing-cover.  The  mature  larva  is 
about  the  same  length  as  the  beetle,  is 
of  light  yellow  color  and  Ls  covered  with 
stout  branched  spines  that  are  black  at 
their  tips,  a  larva  being  shown  at  C, 
Fig.  229.  The  larva  when  fully  grown 
fastens  the  posterior  end  of  its  body  to 
the  under  side  of  a  leaf  and  then  in  a 


Fig.  229.— The  bean  lady- 
bird {Epilachna  varivestis 
Muls.):  a,  adult  beetle;  6, 
pupa;  c,  larva;  (/,  bean  pod 
showing  injury.  (After 
Gillette,  Colo.  Agr.  Exp. 
Sta.) 


*  Epilachna  varivestis  Muls.     Family  Coccinellidce. 
t  Bulletin  19,  Colo.  Agr.  Exp.  Sta.,  p.  25. 


316         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

few  days  sheds  its  outer  skin  containing  the  spines  and  changes  to 
the  pupa  state  (Fig.  229,  B).  From  these  pupae  the  beetles  appear 
a  few  days  later.  They  live  over  winter,  and  appear  about  as 
soon  as  the  beans  are  up  in  the  garden  or  field  and  begin  to  feed 
upon  the  leaves,  on  the  under  side  of  which  they  deposit  their 
yellowish-brown  eggs  in  large  clusters  after  the  manner  of  the 
'Colorado  potato  beetle.'  The  spiny  little  larvse  that  hatch 
from  these  eggs  remain  on  the  under  side  of  the  leaves,  which  they 
skeletonize  in  feeding.  The  beetles  eat  through  the  veins  of  the 
leaves  and  tlo  not  skeletonize  them.  They  also  eat  into  and  destroy 
the  green  pods,  as  shown  in  Fig.  229,  D.  There  is  also  one  brood 
of  this  insect  in  a  season. 

Control. — Paris  green  dusted  upon  the  plants  diluted  with 
100  parts  of  air-slaked  lime  or  flour  is  recommended,  or  it  may  be 
applied  with  Bordeaux  mixture,  1  pound  to  200  gallons,  but  much 
care  must  be  used  not  to  burn  the  foliage,  which  seems  to  be  very 
susceptible  to  the  arsenic.  Arsenate  of  lead  would  probably 
obviate  this.  In  spraying,  an  underspray  nozzle  must  be  used 
to  reach  under  the  leaves.  Dilute  kerosene  emulsion  will  kill 
the  larva?,  but  must  also  be  used  with  caution  to  avoid  injury  to 
the  plant.  Whaleoil  soap  might  be  as  effective  and  less  injurious 
to  the  plant.  Upon  small  gardens  handpicking  of  the  adult 
beetles  as  soon  as  they  appear  in  the  spring  will  probably  be  the 
surest  means  of  combating  them.  Cleaning  up  the  old  patch  and 
plowing  it  under  will  doubtless  aid  in  preventing  successful 
hibernation. 

Blister-beetles. 

Several  species  of  elongate,  grayish,  black  or  bright  green 
blister-beetles  feed  in  large  numbers  upon  bean  foliage.  The 
general  life  history,  ha))its,  and  remedies  have  been  already 
described.     (See  pages  107,  301.) 

2'he  Ash-gray  Blister-beetle  * — This  is  the  most  common  species 
affecting  beans  in  the  East  and  westward  to  Kansas  and  Nebraska. 
The  beetle  is  a  uniform  ash-gray  color  and  of  the  form  shown  in 
*  Macrobasis  unicolor  Kby. 


INSECTS  INJURIOUS   TO    BEANS  AND    PEAS 


317 


Fig.  230.  The  beetles  attack  this  and  other  legumes  in  immense 
swarms,  riddling  the  forest  in  a  few  days  if  not  checked,  and 
appear  from  the  middle  of  June  to  the  middle  of  Juh'. 

NuttaWs  BUster-beefle* — This  species  occui-s  from  the  Miss- 
issippi west  to  the  Rockies,  through  the  region  of  the  Missouri 
\'alley,  and  north  to  the  Northwest  Territories,  where  it  seems  to 
be  particularly  destructive  to  beams,  though  affecting  many 
garden  vegetables.      The  life  history  is  not  known,  but  is  probably 


Fig.  230— The  ash-gray  blister-beetle  Fig.    231.— Nuttall's   blister-beetle 

(Macrobasis  unicolor  Khy.):  iemale  {Cantharis  iiultaUi)  Say:  female 

beetle  at  right,  twice  natural  size;  beetle,  enlarged  one-third.   (After 

male  antenna  at  left,  greatly  en-  Chittenden,  U.  S.  Dept.  Agr.) 
larged.     (After  Chittenden,  U.   S. 
Dept.  Agr.) 

similar  to  that  of  other  species,  as  the  beetles  appear  about  July  1st. 
in  years  following  severe  outbreaks  of  grasshoppers.  Owing  to 
the  rapidity  with  which  this  species  works  and  the  large  numbers, 
poisons  will  be  of  little  avail  and  mechanical  measures  must  be 
employed  for  their  destruction. 
Control.— ^eQ  page  302. 

The  Bean-aphis  f 

"  Crowded  together  in  clusters  upon  the  top  of  the  stalks 
and  under  side  of  the  leaves  of  the  English  bean,  the  puppy 
dahlia,  and  several  other  plants,  a  small   black  plant-louse  with 

*  Cantharis  nuttalli  Say. 

t  Aphis  rumicis  Linn.     Family  Aphididoe- 


318      INSECT  PESTS   OF   FARM,    GARDEN  AND  ORCHARD 

pale  shanks,  the  pupse  with  a  row  of  mealy  white  spots  along  each 
side  of  the  back." — Fitch. 

This  is  an  old  European  pest  of  the  bean,  where  it  is  known  as 
the  black  dolphin,  collier,  and  black  fly.  and  has  sometimes 
caused  the  entire  destruction  of  a  crop.  In  the  United  States 
it  probably  occurs  wherever  beans  are  grown,  having  been  reported 
from  New  York,  Illinois,  Iowa,  Minnesota  and  Colorado.  The 
species  is  probably  best  known  as  affecting  various  species  of 
dock,  upon  the  leaves  of  which  it  occurs  commonly  in  large  num- 
bers. Shepherd's  purse,  pigweed,  the  ''  burning  bush  "  {Euony- 
mus  europoeus  and  atropurpurus) ,  and  the  snowball  bush  are  also 
commonly  infested. 

Life  History. — The  life  history  was  first  described  most  inter- 
estingly by  Dr.  Fitch  in  his  13th  Report  *  and  has  since  been 
confinned  by  Osborne  and  Sii'rine.f  The  eggs  are  laid  in  the  fall 
around  the  buds  of  the  wahoo  or  "  Imrning  bush"  {Euonymus 
atropwpurus),  and  possibly  upon  the  snowball.  The  first  gen- 
eration or  two  multiph'  upon  these  plants  and  then  spread  to 
common  weeds  such  as  shepherd's  purse,  pigweed,  dock,  etc. 
during  the  latter  part  of  May  and  early  June,  from  which  they 
again  migrate  to  Ijeans  when  that  crop  is  available.  During 
the  summer  the  aphides  multiph-  upon  these  food-plants  vivipar- 
ously,  i.e.,  by  giving  birth  to  live  young,  all  being  females,  as  is  the 
rule  with  aphides;  but  al)Out  the  middle  of  September,  in  Iowa, 
winged  males  and  females  migrate  back  to  the  wahoo. 

Description. — The  wingless  females  are  aljout  one-tenth  an 
inch  long,  pear-shaped,  sooty  black,  frequently  marked  with 
pruinose  whitish  dots  along  each  side  of  the  back.  The  antennae 
are  about  half  the  length  of  the  body,  yellowish-white,  except 
toward  the  tips  and  the  two  basal  segments,  which  are  black. 
Honey  tubes  short,  scarceh'  half  as  long  as  from  their  bases  to 
tip  of  abdomen.     Tail  half  as  long  as  the  honey  tubes. 

The    winged   females   are   glossy   black,  one-twelfth  an  inch 

*  Fitch,  13th  Report  on  the  Noxious,  Beneficial  and  other  Insects  of  the 
State  of  New  York,  Trans.  N.  Y.  State  Agr.  Soc,  1869,  p.  495. 

t  Osborn  and  Sirrine,  Bulletin  23,  Iowa  Agr.  Exp.  Sta.,  p.  901,  1894. 


INSECTS   INJURIOUS   TO   BEANS  AND  PEAS  319 

long  to  the  tip  of  the  abdomen  and  twice  that  length  to  the  tip 
of  the  closed  wings.  The  a])domen  lacks  the  white  spots  of  the 
wingless  females  and  pupa?.  Legs  are  black,  except  shanks, 
which  are  whitish  with  dark  tips.  Otherwise  the  winged  form 
resembles  quite  closely  the  wingless  form.  The  black  color 
and  white  spots  on  the  abdomen  of  the  wingless  females  and 
pupte  will  readily  distinguish  the  species  from  other  aphides  on 
beans. 

Control. — Spraying  with  dilute  kerosene  emulsion  has  proven 
the  best  means  of  combating  the  pest  according  to  Osborn  and 
Sirrine,  diluting  the  stock  solution  fifteen  times,  or  so  the  spray- 
ing mixture  will  contain  al^out  5  per  cent  of  kerosene.  It  seems 
that  the  foliage  of  the  bean  is  quite  susceptible  to  injury  from  any 
free  kerosene,  and  probably  whaleoil  soap  1  pound  to  5  or  6  gal- 
lons, would  prove  safer  and  equally  efficient.  As  it  is  frequently 
necessary  to  spray  beans  with  Bordeaux  mixture  or  other  fun- 
gicides for  fungous  diseases,  the  whaleoil  soap  might  be  readily 
sprayed  at  the  same  time. 

•  '^      The  Gray  Hair-streak  Butterfly  * 

The  caterpillars  of  the  Gray  Hair-streak  Butterfly  have  been 
noticed  injuring  beans,  peas  and  cow-peas,  for  a  number  of  years 
throughout  the  United  States,  but  the  injury  is  usually  local  and 
not  often  serious.  The  caterpillar  is  about  one-half  an  inch  long, 
decidedly  flattened,  somewhat  oval,  bright  green,  with  head 
retracted  in  the  thorax,  and  covered  with  short  hairs,  which  give  it 
a  velvety  appearance.  The  adult  butterfly  is  a  handsome  bluish- 
black  butterfly  with  red  anal  spots  as  shown  in  Fig.  177.  The 
caterpillar  has  been  a  serious  enemy  of  hops,  and  in  the  South 
attacks  cotton  square  •!,  being  termed  the  cotton  square-borer, 
but  the  pods  of  legumes  seem  to  be  the  preferred  food.  Where 
injury  recurs,  thorough  spraying  with  Paris  green  or  arsenate 
of  lead  as  the  pods  are  forming  will  doubtless  hold  the  larvae  in 
check,  as  the  eggs  are  laid  upon  the  foliage  and  the  young  larvae 

*  Uranotes  jnclinus  Hubn.     Family  Lyccenidoe. 


320       INSECT  PESTS  OF   FARM,   GARDEN   AND  ORCHARD 

feed  somewhat  upon  it  and  will  secure  enough  of  the  surface  of 
the  pods  in  entering  to  effectively  poison  them  if  the  pods  are  well 
coated.* 

The  Seed-corn  Maggot  j 

This  insect  has  been  termed  the  Seed-corn  Maggot  on  account 
of  its  frequent  injuries  to  early  seed-corn,  but  in  recent  years  it 
has  often  seriously  injured  the  seeds  of  beans  and  peas,  on  account 
of  which  it  has  been  termed  the   "  bean-fly,"    while    cabbage, 


Fig.  232. — Seed-corn  maggot  {Pegomya  fusciceps):  a,  male  fly,  dorsal  view; 
b,  female,  lateral  view;  c,  head  of  female  from  above;  d,  larva,  from  side; 
e,  anal  segment  of  larva;  /,  anal  spiracles;  g,  cephalic  spiracles:  h,  pupa- 
rium — all  much  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

turnip,  radish,  onions,  beets  and  seed  potatoes  are  among  its 
other  food-plants. 

The  species  is  of  European  origin,  and  was  first  noted  in  this 
country  by  Dr.  Asa  Fitch  in  1856.  Since  then  it  has  become 
distributed  throughout  tho  United  States  from  Minnesota  to 
Texas  and  eastward. 

The  adult  flics  closely  resemble    the    root-maggots   affecting 

*  See  "  In.sect  Life,"  Vol.  VII,  p.  354.  Chittenden,  Bulletin  33,  Div.  Ent., 
U.  S.  Dept.  Agr.,  p.  101;  Sanderson,  Farmers'  Bulletin,  U.  S.  Dept.  Agr., 
223,  p.  17,  and  Bulletin  57,  Bureau  Entomology,  p.  40. 

f  Pegomya  fusciceps  Zett.     Family  AnthomyidoB. 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS  321 

the  cabbage  and  onion  and  arc  about  one-fifth  an  inch  long. 
The  male  may  be  distinguished  from  nearly  related  species  by  a 
row  of  nearly  equal,  short  bristles  on  the  inner  side  of  the  hind 
tibiae  or  shanks. 

The  life  history  of  the  species  has  not  been  carefully  observed, 
but  is  probably  similar  to  that  of  other  root-maggots.  The 
flies  deposit  their  eggs  either  upon  the  young  seedling  just  as  it 
appears  above  ground,  or  probably  more  often  on  the  seed  itself. 
Injury  is  called  to  attention  by  the  seed  failing  to  germinate, 
which,  when  examined,  is  found  to  contain  one  or  more  small 
white  maggots,  which  have  destroyed  the  germ  or  the  young 
seedling.  Thus  in  1895,  large  areas  of  beans  were  destroyed  in 
Minnesota.* 

The  maggots  are  about  one-fourth  an  inch  long,  slightly 
smaller  than  the  onion-maggot,  from  which  they  may  be  dis- 
tinguished by  the  tubercles  of  the  anal  segment. 

Control. — It  has  been  noted  that  injury  often  occurs  where 
stable  manure  has  been  turned  under,  and  it  may  be  possible 
that  the  flies  are  attracted  to  it  to  oviposit  or  that  they  are 
attracted  by  decaying  seed.  In  preventing  attacks  of  root- 
maggots  it  would  seem  advisable  to  apply  stable  manure  the 
previous  fall  so  that  it  may  become  well  rotted  and  incorporated 
into  the  soil  before  seeding.  Rolling  the  seed-bed  after  planting 
might  also  be  of  value  in  preventing  the  access  of  the  flies  to  the 
seed. 

Applications  of  commercial  fertilizers  which  will  ensure  a 
.  quick  growth  of  the  seedling  are  advisable.  The  use  of  carbolic  acid 
emulsion  and  sand  and  kerosene  upon  the  surface  of  the  seed-bed 
after  planting  and  as  the  seedlings  are  appearing,  as  advised 
for  the  cabbage  root-maggot  (see  page  352) ,  will  also  be  of  value. 
Inasmuch  as  the  injury  is  sporadic  and  affects  the  seed  before  it 
can  be  readily  detected,  reliance  must  be  placed  chiefly  upon 
general  cultural  methods  as  outlined  above  and  others  which 

*  See  Lugger,  Bulletin  43,  Minn.  Agr.  Exp.  Sta.,  p.  207  (1st  Rept.  Minn. 
State  Entomologist.)  See  Circular  63,  and  Bulletin  33,  p.  S4,  Bureau  of 
Entomology,  U.  S.  Dept.  Agr. 


322       INSECT   PESTS  OF   FARM,   GARDEN  AND  ORCHARD 

a  better  knowledge  of  the  life  history  of  the  pest  will  undoubtedly 
suggest. 

The  Pea-aphis  * 

Large  green  plant-lice  often  become  so  abundant  on  the  foliage 
and  pods  of  garden-peas  as  to  completely  kill  the  plants.     Prior 




-^ 

^ 

•"^""^ 

fCZT      ' 

'~'~7~7-~~-^^fcr 

^--  -"'^ 

<?=7'/ 

r 

\ 

N 

1 

\ 

^ 

\ 

\ 

mSb 

V 

Fig.  233.— The  pea-aphis  (Macrosiphum  pisi  Kalt):    winged  and  wingless 
viviparous  females  and  young — enlarged. 

to  1899  the  pea-aphis  had  not  been  a  serious  pest  in  this  country, 
but  during  that  and  the  following  season  it  caused  a  loss  of  several 
million  dollars  to  pea-growers  on  the  Atlantic  coast  from  North 

*  Macrosiphum  pisi  Kalt.  P'amily  Aphididce.  See  Chittenden,  Circular 
43,  Bureau  of  Ent.,  U.  S.  Dept.  Agr.;  Sanderson,  Bulletin  49,  Del.  Agr.  Exp. 
Sta.;  Folsom,  Bulletin  134,  111.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO   BEANS   AND  PEAS  323 

Ciirolina  to  Nova  Scotia  and  as  far  west  as  Wisconsin,  especially 
where  peas  were  extensively  grown  for  canning.  During  1901 
injury  was  by  no  means  as  serious,  and  has  materially  decreased 
since  then,  though  sporadic  injury  occurs  almost  every  year  in  some 
section.  General  injury  occurs  only  periodically  for  reasons  men- 
tioned below.  The  pest  seems  to  occur  throughout  the  States  east 
of  the  100th  meridian  and  possibly  further  west.  It  is  an  old 
enemy  of  peas  in  England,  where  it  destroyed  the  crop  as  long  ago 
as  1810,  and  it  has  long  been  known  in  Europe  as  an  enemy  of 
peas,  clovers,  vetches  and  related  plants. 

Both  wingless  and  winged  aphides  occur  together  throughout 
the  season,  the  latter  predominating  whenever  food  becomes  scarce. 
The  winged  forms  are  from  one-eighth  to  one-seventh  of  an  inch 
long,  with  wings  expanding  two-fifths  of  an  inch.  The  body  is  a 
pea-green  color,  light  brownish  between  the  wings  and  on  the  head, 
the  eyes  are  red,  and  the  legs,  antenna  and  honey  tubes  are  yellow- 
ish, tipped  with  lilack.  The  wingless  females  are  similar  in  size  and 
color,  but  are  much  broader  across  the  abdomen,  and  the  honey 
tubes  are  somewhat  larger.  The  mouth-parts  of  the  pea-aphis  are 
of  the  sucking  type,  and  it  secures  its  food  by  puncturing  and  suck- 
ing up  the  juices  of  the  plant.  The  plant  is  thus  injured  by  the 
large  numljer  of  aphides  sucking  out  its  juices  and  causing  it  to 
wilt  and  die. 

Life  History. — The  aphides  pass  the  winter  on  clover  and 
vetches,  and  often  increase  upon  clover  so  as  to  do  it  serious 
injury,  as  described  on  page  211.  Where  peas  area  vailable  the 
winged  females  usually  migrate  to  them  about  the  time  peas  are 
6  or  S  inches  high,  and  give  birth  to  live  young,  which  develop  into 
wingless  viviparous  females.  These  females,  as  do  those  of  sub- 
sequent broods  throughout  the  summer,  give  birth  to  live  young, 
and  reproduction  goes  on  at  a  rapid  rate.  According  to  the  obser- 
vations of  Mr.  R.  L.  Webster,  in  central  Illinois,  an  aphid  becomes 
grown  about  eleven  days  after  it  is  born,  lives  about  twenty-five 
days  and  gives  birth  to  about  fifty  young,  though  under  favorable 
conditions  over  one  hundred  are  frequently  born.  Sixteen  genera- 
tions have  been  observed  from  March  23d  to  October  4th.  Winged 


324      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

aphides  develop  as  often  as  the  food-plant  becomes  overcrowded 
and  it  is  necessary  to  migrate  to  avoid  starvation. 

By  midsummer,  with  the  harvesting  of  the  peas,  most  of  the 
aphides  upon  them  have  been  destroyed  by  prcdaceous  and  para- 
sitic insects  and  disease,  and  they  are  not  observed  during  late  sum- 
mer unless  they  have  been  subsisting  on  clover  throughout  the 
season,  when  they  sometimes  destroy  the  crop  in  August,  as  has 


Fig.   234. — The   pea-aphis   on   stems   of  red   clover — ^natural   size.     (After 

Folsom.) 


been .  observed  in  Illinois.  In  early  fall  they  often  become  com- 
mon again  on  late  garden  peas,  and  late  in  October  they  migrate 
to  clover.  Fewer  young  are  born  as  the  weather  gets  colder  in 
the  fall,  and  the  aphides  never  become  numerous  enough  to  do  any 
injury  at  that  season.  Late  in  October  and  early  November — in 
the  Middle  States — as  the  aphides  are  migrating  to  clover,  winged 
males  appear,  and  some  of  the  wingless  females  developing  on 
clover  produce  eggs.    The  winged  males  are  similar  in  size  and  color 


INSECTS  INJURIOUS  TO  BEANS  AND   PEAS  325 

to  the  migratory  females,  tliougli  slightl}-  darker,  and  have  three  or 
four  dark  spots  along  the  sides  of  the  abdomen  and  a  deep  brown 
dash  on  either  side  of  the  back  of  each  abdominal  segment.  The 
oval  eggs  are  about  one-fiftieth  inch  long,  jet  black,  and  are 
deposited  on  the  lower  leaves  or  stems  of  clover,  and  hatch  as  it 
commences  to  grow  in  the  spring.  In  central  Illinois  they  were 
observed  to  hatch  March  23d,  and  the  young  became  full  grown 
and  commenced  reproduction  on  April  5th,  living  until  May  12th. 
In  southern  i\Iar}'land  and  further  south  many  of  the  viviparous 
females  live  over  winter  on  the  clover  and  commence  to  reproduce 
again  in  the  spring,  no  eggs  having  been  observed  in  that  latitude, 
but  in  central  Illinois  and  northward,  the  females  are  probably 
entirely  destroyed  by  the  cold  and  only  the  eggs  survive. 

Natural  Enemies. — From  5  to  10  per  cent  of  the  aphides  are 
normally  destroyed  by  little  wasp-like  flies  of  the  genus  Aphidius, 
whose  larvae  live  within  the  aphides.  A  number  of  the  more  com- 
mon ladybird-beetles,*  syrphus-flies,tand  lace-winged  flies,|  which 
commonly  prey  upon  aphides,  destroy  large  numbers  of  the  pests, 
but  their  work  comes  so  late  in  the  season  that  the  peas  are  seri- 
ously injured  long  before  the  aphides  are  checked  by  them,  though 
they  might  prevent  a  reappearance  the  next  year. 

The  most  important  enemy  of  the  pea-aphis  is  a  fungous  dis- 
ease {Empusa  aphidis)  which  is  undoubtedly  the  principal  factor 
in  its  natural  control.  The  most  probable  explanation  of  the 
remarkable  outbreak  of  the  pea-aphis  in  1899  and  1900  seems  to  be 
that,  due  to  two  exceptionally  dry  springs,  the  fungus  Avas  unable 
to  develop,  as  it  propagates  best  in  damp  weather,  and  the  aphides 
increased  unchecked.  Though  occasional  individual  aphides  were 
found  killed  by  the  fungus  early  in  the  season,  not  until  June  11, 
1900,  were  diseased  aphides  found  in  any  quantity,  but  after  that 
so  swiftly  did  the  disease  destroy  them  that  a  week  later  but  few- 
aphides  were  to  be  found  and  almost  all  were  diseased.  Probably 
this  fungus  usualh'  destroys  th(>  aphides  on  clovei-  before  they  have 
become  excessively  numerous  or  have  migi'ated  to  peas. 

*  Family  CoccinelUdce.  ■  t  Family  Syrphidce. 

X  Family  ChrysopidcB.     Concerning  these  predaceous  insects,  see  p.  D. 


326       INSECT  PESTS  OF   FARM,   GARDEN   AND  ORCHARD 

Control. — Inasmuch  as  the  aphides  spread  from  peas  to  clover, 
the  latter  crop  should  not  be  planted  near  peas  when  avoidable. 
In  the  spring  the  aphides  should  be  carefully  observed  on  the 
clover  and  if  they  become  excessively  al^undant,  the  only  way  to 
prevent  their  migration  to  peas  is  to  plow  under  the  clover  deeply 
and  roll  the  field. 

Highly  fertilized  land  in  which  the  moisture  is  retained  by  fre- 
quent cultivation  very  often  enables  a  crop  to  mature  in  spite  of 
moderate  injur}-.  Peas  sown  broadcast  or  planted  in  8-inch 
drills  have  been  much  more  seriously  injured  than  those  planted 
in  rows  18  to  30  inches  apart  and  cultivated,  and  those  planted 
close  together  afford  no  opportunity  for  l^rushing  or  cultivating 
as  described  below. 

Early  varieties  of  peas  have  practically  escaped  injur)'  where 
late  varieties  have  been  wholly  destroyed,  so  that  it  is  obvious  that 
only  the  earliest  varieties  should  l)e  grown  whoi-o  injury  is  antici- 
pated. 

Early  in  1900  Professor  W.  G.  Johnson  found  that  when  peas 
were  planted  in  rows  that  the  aphides  could  be  readily  knocked  from 
the  vines  by  means  of  brushing  with  a  l^ranch,  and  that  by  follow- 
ing the  brushes  with  cultivators,  the  aphides  would  be  covered  with 
earth  and  destroyed,  either  by  suffocation  or  by  the  heat  of  the 
soil.  Where  the  air  temperature  is  95°  F.  the  soil  will  be  nearly 
120°,  and  aphides  brushed  onto  it  will  be  actually  roasted  to  death 
in  a  few  minutes.  The  cultivation  should  not  be  repeated  for 
about  three  days,  as  it  requires  about  that  time  for  the  destruction 
of  the  insects  covered  with  earth,  if  it  is  not  hot  enough  to  kill 
them  at  once.  By  this  method  large  areas  of  peas  have  been  saved 
from  destruction,  but  it  was  found  that  where  the  soil  was  moist 
it  would  form  small  clods  after  cultivation  and  that  the  aphides 
would  merely  crawl  out  from  under  them. 

To  meet  this  difficulty  Professor  Johnson  devised  a  pan  into 
which  the  aphides  might  be  brushed  and  destroyed.  This  pan  is  mod- 
elled after  the  hopper-dozers  used  in  the  West  for  catching  grass- 
hoppers, and  consists  of  a  long,  shallow  pan,  the  width  of  the  dis- 
tance between  the  rows  and  5  or  6  inches  deep.     A  little  water  is 


INSECTS  INJURIOUS  TO  BEANS  AND  PEAS  327 

placed  in  the  bottom  and  covered  with  a  film  of  kerosene.  The 
pan  is  drawn  between  the  rows  wdiile  a  boy  on  each  side  brushes 
the  aphides  into  it  with  a  branch  as  shown  in  Fig,  235.  The  pans 
are  easily  made  from  galvanized  iron  and  may  be  operated  at 
small  cost. 

Though   the   above   methods   will   destroy   quantities   of   the 
aphides  and  thus  prevent  the  destruction  of  the  crop,  they  do  not 


Fig.  235. — Showing  the  structure  of  pan  and  use  of  it  with  brushes  against 
the  pea  louse.     This  field  was  saved  by  its  use.     (After  W,  G.  Johnson.) 

dislodge  the  3'oung  aphides  in  the  terminals,  and  therefore  cannot 
be  relied  upon  to  prevent  all  injury.  Practical  field  tests  have 
shown  that  this  may  be  done  Ijy  spraying  with  whale-oil  soap,  1 
pound  to  G  gallons  of  water.  In  small  gardens  this  may  be  applied 
by  means  of  bucket  or  knapsack  pumps,  and  on  small  acreages 
with  a  barrel  sprayer  with  a  row-spraying  attachment  having  noz- 
zles arranged  so  that  the  vines  will  be  thoroughly  covered  from 
each  side.     The  spray  must  be  applied  with  considerable  pressure 


328      INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 

so  as  to  force  it  into  the  terminals.  For  large  fields  a  New  Jersey 
grower  devised  a  traction  sprayer  covering  three  rows  *  which 
applied  the  material  at  a  cost  of  $2.50  an  acre  for  labor  and  materials. 
To  be  effective  spraying  should  be  commenced  as  soon  as  aphides 
are  found  generally  distril^uted  over  the  plants.  Kerosene  emul- 
sion may  be  used  on  a  small  scale,  if  carefully  made,  but  more  or 
less  injury  has  resulted  where  it  has  l)een  used  extensively.  Prob- 
ably many  of  the  tobacco  preparations  now  on  the  market  would 
effectively  destroy  the  aphides  and  would  not  injure  the  vines. 


The  Pea-moth  f 

The  Pea-moth  is  an  old  pest  in  Europ(>,  whence  it  was  imported 
into  Canada,  where  it  has  frequently  done  considerable  mischief. 

It    is    known    to    occur  in    the 


fA^ 


"~r    /r 


IS 

large  pea-growing  sections  of 
New  Brunswick,  Nova  Scotia 
and  Ontario,  where  it  first  at- 
tracted attention  near  Toronto 
in  1898,  and  was  found  in  the 
pea-growing  section  of  Michigan 
in  1908.  The  Avings  of  the  adult 
moth  expand  al:)Out  one-half 
an  inch,  the  fore-wings  being 
"  dark,  fuscous  or  dusky,  tinged 
with  darker  brown  and  mottled 
with  white,"  the  hind- wings 
being  a  uniform  fuscous  with  a 
rather  long  inner  fringe  of  hairs,  as  shown  in  Fig.    36. 

The  females  may  be  found  flying  around  pea-blossoms  soon 
after  sunset,  and  deposit  one  to  three  eggs  on  young  pods.  The 
caterpillar  hatches  in  about  fourteen  days,  according  to  European 
observations,  and  attacks  the  forming  seed.  Affected  pods  usu- 
ally ripen  early.  The  larva  is  whitish-yellow  with  a  pale  brown  head 

*  For  description  and  figure,  see  13th  Annual  Rept.  Del.  Agr.  Exp.  Sta., 
pp.  168-172. 

f  Semasia  nigricann  Steph.     Family  Tortricidce. 


Fig.  236. — The  pea-moth  {Semania 
nigricana  Steph.):  moth  above, 
larva  below — about  three  times 
natural  size.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  BEANS   AND  PEAS  329 

and  thoracic  plate,  and  about  one-half  an  inch  long  when  full 
grown.  With  the  opening  of  the  pod  the  larva  crawls  out  and 
enters  the  earth,  where  it  spins  a  very  thin  silken  cocoon.  The 
length  of  the  pupal  stage  and  the  method  of  hibernation  do  not 
seem  to  be  well  established,  ^'er}•  early  and  very  late  varieties 
are  but  little  injured. 

Remedies. — This  suggests  one  of  the  best  means  of  handling 
this  pest  to  be  the  growing  of  early  varieties,  such  as  Alaska, 
American  Wonder,  Gregory's  Surprise,  Xott's  Excelsior,  and 
McLean's  Little  Gem.  If  the  crop  is  known  to  be  infested,  clean 
up  the  vines  and  Ijurn  them  as  soon  as  it  is  picked.  Dr.  Fletcher 
has  made  some  experiments  in  spi'aying  for  this  pest  which  seem 
to  promi.se  success.  One  pound  of  Paris  green  to  100  gallons  of 
water  was  used,  and  it  is  advised  to  spra}-  three  times;  the  first 
when  the  bloseoms  begin  to  fall;  the  second,  a  week  later;  and  the 
third  ten  days  later  than  that. 


CHAPTER  XVII 
INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH* 

The  Beet-aphis  t 

This  species  was  first  doscrilxHl  by  JMr.  W.  R.  Doane  in  1900 
and  seems  thus  far  to  have  Ix-eii  found  only  in  Washington  and 
Oregon.  "  Attention  was  first  called  to  this  pest,"  he  says,J  "  in 
1896,  when  it  was  found  that  a  field  of  two  or  three  acres  of  beets 
was  generally  infested,  a  strip  of  twenty-five  to  a  hundred  yards 
being  so  badly  injured  that  the  Ijeets  were  nearly  all  soft  and 
spongy,  and  the  plants  much  smaller  than  the  average. 

"  It  has  been  even  more  destructive  in  Oregon  than  in  Wash- 
ington, at  least  a  thousand  tons  of  beets  having  been  destroyed  by 
it  in  one  year  in  a  single  valley  devoted  largely  to  beet-culture. 
Like  very  many  other  beet-insects,  this  species  infests  also  several 
wild  or  useless  plants. 

"  The  smaller  rootlets  of  the  beet  are  first  attacked  by  this 
aphis,  and  if  it  occurs  in  considerable  numbers  these  are  soon  all 
destroyed,  and  the  leaves  thereupon  soon  wither,  and  the  whole 
beet  shrivels  and  becomes  spongy.  This  wilting  of  the  leaves  will 
frequently,  in  fact,  be  the  first  thing  to  attract  the  attention  of  the 
beet-grower.  The  actual  injury  to  the  crop  will,  of  course,  depend 
largely  upon  the  time  when  the  attack  of  the  aphis  is  made.  If  the 
plants  are  small  they  may  be  readily  destroyed,  while  if  they  are 
practically  full  grown  the  loss  of  the  small  rootlets  will  not 
materially  affect  them. 

*  See  Forbes  and  Hart,  Bulletin  60,  111.  Agr.  Exp.  Sta.,  and  F.  H.  Chitten- 
den, Bulletin  43,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr. 
t  Pemphigus  betce  Doane.     Family  Aphidoe. 
X  Bulletin  No.  42,  Wash.  Agr.  Exp.  Sta. 

330 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH 


331 


"  No  sexual  generation  of  this  aphis  has  as  yet  been  discovered 
;;;nd  no  eggs  have  been  seen,  viviparous  rcprotluction  continuing 
throughout  th(^  year  except  when  the  cold  of  the  winter  tempora- 
rily suspends  the  physiological  activities  of  the    species.      The 


Fig.  237. — The  beet-aphis    (Pemphigus  betae  Doane) :   a,  winged  female;    6, 
wingless  female;  c,  antenna  of  winged  female.     (After  Doane.) 

winged  females,  appearing  from  time  to  time  during  the  summer 
and  fall,  serve  to  distribute  the  species  generally,  new  colonies 
being  started  wherever  these  females  find  lodgment  and  food.  In 
districts  liable  to  injury  Ijy  this  insect  it  seems  inadvisable  that 
beets  should  b(^  the  first  crop  on  new  land,  or  that  ground  should 

be  continued  in  beets  or  in  any  other 
root-crop  after  the  pest  has  made  its 
appearance  in  the  field." 

y(F^%t  J^  Another  plant-louse,  called  the  beet 

*=*^  11      Vi^^^-Nx  root-aphis  *,  proved  injurious  to  sugar- 

beets  in  Colorado  in  1903.  They  were 
found  ''  quite  generally  distributed  in 
the  beet-fields  in  the  vicinity  of 
Rockyford  and  attacking  the  roots  of 
man}-  weeds."  What  seemed  to  be  this 
species  was  very  abundant  upon  the 
roots  of  the  common  garden  purslane, 
to  which  it  was  very  injurious.  Near 
*  Tychea  brevicornis  Hart. 


Fig.  238.— Beet  root-aphis 
{Tychea  brevicornis  Hart) : 
a,  aphis;  b,  antenna;  c, 
tarsus— all  greatly  enlarged. 
(After  Garman). 


332      INSECT  PESTS  OF   FARM,   GARDEN  AND   ORCHARD 

Fort   Collins    a    badly    infested    field    of    sugar-beets  was  also 
seriously  damaged. 

No  practical  means  for  controlling  these  pests  seems  to  have 
been  recorded,  so  that  in  case  of  injury  the  entomologist  of  the 
State  should  ho  consulted. 

White  Grubs,  Wireworms,  and  Cutworms 

Fortunately  for  the  sugar-l^ect  farmer  the  worst  insect  ene- 
mies of  that  plant  feed  upon  the  tops,  and  very  rarely  do  we  hear 
of  serious  damage  being  done  the  roots.  In  the  East  most  of  the 
damage  to  the  roots  is  done  by  those  familiar  old  farm-thieves,  the 
white  grul),  the  cutworm  and  the  wire  worm.  As  a  general  rule 
they  will  be  found  to  be  worse  on  lands  previously  in  sod,  which 
should  therefore  be  avoided  when  known  to  be  badly  infested  with 
either  of  these  insects,  as  both  are  difficult  to  fight  after  they  have 
once  commenced  doing  noticeable  injury. 

The  life  histories  and  means  of  control  for  these  pests  will  be 
found  discussed  on  pages  79,  84,  85. 

The  Sugar-beet  Webworm  * 

The  sugar-beet  webworm  is  very  similar  to  the  garden  web- 
worm (page  406),  and  is  so  named  because  it  has  developed  as  a 
serious  pest  of  the  sugar-beet  in  Kansa-s,  Nebraska,  and  Colorado. 
It  has  been  noted  as  injuring  tansy  in  Michigan,  and  feeds  on 
cabbage,  onions,  and  alfalfa,  as  well  as  pigweed  (Chenopodium 
album)  and  careless  weed  (Amaranthus)  and  will  probably  feed 
on  many  other  crops.  It  is  a  native  of  western  and  central 
Europe,  and  northern  Asia,  and  was  evidently  introduced  on  the 
Pacific  Coast,  as  it  was  noted  in  Utah  in  1869. 

The  moth  is  larger  than  the  garden  webworm,  having  a  wing 
expanse  of  an  inch,  and  is  a  purplish-l:)rown  color  with  darker 
and  paler  bands  as  shown  in  Fig.  239.  The  full-grown  larva  is 
about  an  inch  long,  of  a  dark  color  with  a  white  stripe  down  the 

*  Loxostege  sticticalis  Linn.  Family  Pyraustidoe.  See  C.  P.  Gillette, 
Bulletin  98,  Colo.  Agr.  Exp.  Sta.,  and  references  there  given. 


INSECTS  INJURIOUS  TO   BEETS  AND  SPINACH 


333 


back   and   one   along  either  side,   and  marked  with   numerous 
black  and  white  tubercles  as  illustrated. 

Life  History. — The  larvae  hibernate  over  winter  an  inch  or 
two  below  the  surface  of  the  soil  in  long  silken  tubes.  In  spring 
they  pupate  in  these  tubes  and  the  moths  emerge  about  the  middle 
of  May.     The  eggs  are  laid  on  the  foliage  either  singly  or  in  clus- 


FiG.  239. — The  sugar-beet  webworm  (Loxostege  sticticalis  Linn.):  1,  moth;  2, 
eggs;  3,  4,  larvae;  5,  pupa;  6,  winter  tube  of  larva,  opened  at  a  to  show 
pupa — 1,  3,  4,  5,  enlarged.     (After  Gillette,  Colo.  Agr.  Exp.  Sta.) 

ters  of  from  three  to  ten,  one  overlapping  another.  The  egg 
is  broadly  oval,  one  twenty-fifth  inch  long,  and  of  a  pale 
green  color.  The  first  generation  of  caterpillars  feed  on  pig- 
weed and  alfalfa  in  Colorado  during  June.  A  second  generation 
of  larvse  occurs  about  the  middle  of  July  and  sometimes  injures 
beets,  but  the  third  generation  about  the  middle  of  August  is 


334      INSECT  PESTS   OF  FARM,  GARDEN  AND  ORCHARD 

the  one  most  injurious  in  Colorado.  Most  of  these  larvae  hibernate 
over  winter,  but  there  is  a  partial  fourth  generation  in  Colorado- 
The  larvise  defoliate  the  plants,  and  cover  them  with  a  web  the 
same  as  the  native  garden  webworm,  with  which  the  life  history 
seems  to  be  practically  identical. 

Control. — The  same  means  of  control  as  for  the  garden  web- 
worm are  advised. 


The  Beet  Army  Worm  * 

"  This   caterpillar,   which   replaces  the  fall   army  worm    (L. 
frugiperda — see  page  118)  in   the   Western   States,   differs   from 


Fig.  240. — The  beet  army  worm  {Laphijgma  exigua  Hiibn.):  a,  moth;  h, 
larva,  side  view;  c,  larva  ,  back  view;  fZ,  head  of  larva;  e,  egg  from  above; 
/,  egg  from  side — all  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

it  by  its  more  decidedly  mottled  ground-color,  by  a  row  of  white 
dots  at  the  lower  margin  of  the  lateral  dark  band,  and  by  the 
yellower  color  of  the  light  stripes.  It  is  an  interesting  fact  that 
while  the  preceding  species  was  doing  serious,  unusual,  and  wide- 
extended  injury  in  the  Eastern  and  Southern  States  (1899), 
the  present  one  was  similarly  abundant  in  Colorado,  where, 
besides    destroying  many  kinds  of  weeds  and  grasses,  it   com- 

*  Laphygma  exigua  Hbn.     Family  Nociuidce. 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  835 

pletoly  defoliated  thousands  of  acres  of  sugar-beets.  In  some 
cases  where  the  foliage  of  the  beet  did  not  furnish  it  sufficient 
food,  the  root  was  attacked  antl  the  upper  surface  was  com- 
pletely gnawed  away.  Late  plantings,  of  course,  suffered  most 
severely,  especially  when  surrounded  by  newly  jjroken  ground. 
The  weeds  most  generally  eaten  were  pigweed,  saltweed,  wild 
sunflower,  and  Cleome.  Potato,  pea,  and  apple  leaves  were 
also  devoured.  These  injuries  occurred  about  the  middle  of 
August,  at  which  time  the  larva?  and  pupa;  were  abundant,  and 
a  few  moths  laden  with  eggs  were  noticed." 

This  species  evidenty  hibernates  as  a  moth,  and  at  least 
two  broods  of  larvae  may  be  looked  for  each  year,  the  first  about 
June  and  the  second  in  August.  The  species  has  been  reported 
thus  far  from  Colorado  and  California,  ])ut  it  doubtless  has  a 
more  extended  range  in  the  mountain  regions  of  the  far  West. 

"  Professor  Gillette's  field-experiments  showed  that  it  could  be 
destroyed  by  dusting  or  spraying  arsenical  poisons  on  the  leaves." 

Flea-beetles 

Several  species  of  flea-beetles,  chiefly  Systena  tocniata,  Systena 
hudsonias,  Disonycha  triangularis,  and  Phyllotreta  vittata,  often 
do  considerable  injury  l)y  gnawing  small  holes  in  the  upper  and 
lower  surfaces  of  the  leaves,  giving  them  an  appearance  as  if 
affected  by  leaf-spot,  or  puncturing  them  full  of  small  holes,  and 
thus  st\mting  the  growth  of  the  plant. 

The  Spinach  Flea-beetle  * 

Of  the  many  species  of  flea-beetles  injurious  to  sugar-beets, 
the  spinach  flea-l^eetle  is  one  of  the  largest  and  most  destructive. 
The  beetle  is  nearly  one-cjuarter  inch  long,  shining  black,  with 
a  greenish  or  bluish  lustre.  The  prothorax  and  abdomen  are 
red  or  reddish  yellow,  and  the  legs  and  antennae  are  pale  yellowish. 
It  occurs  from  New  England  to  Montana  and  sovithward  to  the 

*  Disonycha  xanthomelcena  Dalm.  Family  ('hry-wmdidce.  See  F.  H. 
Chittenden,  Bulletin  43,  Bureau  of  Ent.,  U.  S.  Dept.  Agr.,  p.  U;  S.  A.  Forbes, 
21st  Kept.  State  Ent.  of  111.,  p.  116. 


336         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Gulf,  and  is  one  of  the  most  common  pests  of  beets  and  spinach, 
while  its  native  food  plants  are  chickweed  and  lambsquarters. 

Life  History. — The  Ijeetles  hibernate  over  winter  and  emerge 
in  the  spring  during  April  and  May.  The  Iniff  or  orange  eggs  are 
laid  on  end  in  small  masses,  "at  the  bases  of  the  plants  infe  ted, 
on  bits  of  leaf  or  earth,  or  even  Avithin  the  earth  "  according  to 
Forbes.  The  eggs  hatch  from  sometime  in  April  to  early  July, 
according  to  locality.     The  larva'  usually  feed  on  the  under  side 


Fig.  241. — The  sp'nach  flea-beetle  {Disonycha  xanthomeloena  Dalm.):  a, 
beetle;  6,  egg  mass;  6b,  sculpture  of  egg;  c,  larva;  d,  pupa;  e,  young  larva; 
/,  abdominal  segment  of  same — o,  c,  d,  five  times  natural  size;  h,  more 
enlarged;  66,/,  highly  magnified.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

of  the  leaf,  keeping  together  in  families  which  migrate  from  leaf 
to  leaf  while  young,  and  drop  to  the  ground — as  do  the  beetles — • 
when  disturbed.  While  young  they  merely  gnaw  the  under 
surface  of  the  leaf,  but  later  they  eat  through  and  riddle  it  with 
round  holes,  in  which  they  are  aided  by  the  beetles.  The  full- 
grown  larva  is  about  one-quarter  inch  long,  of  a  dull  gray 
color,  except  on  red  and  pui-i)l('  beets,  on  which  it  assumes  the 
color  of  the  plant  attacked,  is  of  a  c}'lindncal  form,  and  the  seg- 
ments are  strongly  marked  by  rows  of  raised  tubercles,  each  of 
which  bears  a  black  hair  at  the  tip.     The  larva3  become  grown 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH  337 

in  late  June  and  early  Jul}-  in  Illinois,  and  enter  the  earth  to 
pupate,  the  beetles  of  the  next  generation  emerging  about  a 
month  after  the  eggs  were  deposited.  The  beetles  of  the  second 
generation  lay  their  eggs  from  July  to  September  and  the  beetles 
mature  before  winter  sets  in.  In  the  District  of  Columbia, 
Chittenden  observes  that  the  first  generation  is  more  abun- 
dant on  chickweed  and  the  second  is  injurious  to  beets  and 
spinach. 

Control. — Thoroughly  dusting  or  spraying  the  plants  with 
Paris  green  or  preferably  arsenate  of  lead  will  readily  destroy 
the  larvae  and  probably  most  of  the  beetles.  As  in  combating 
all  flea-beetles  the  destruction  of  the  weeds  upon  which  they 
multiply  is  important. 

The  Larger  Beet  Leaf -bee  tie  * 

One  of  the  principal  pests  of  the  sugar-beet  in  Colorado  and 
adjacent  States  is  a  rather  large  brownish  leaf-beetle  which  with 
its  larvae  destroy  the  foliage  or  so  injure  it  that  the  plant  dies. 
It  is  often  locally  known  as  the  "  alkali  bug  "  from  the  fact  the 
injury  is  mostly  on  alkali  soil  or  land  near  it,  and  "  french  bug,'' 
prol)ably  from  the  "  frenching  "  of  the  foliage.  The  beetle  is 
from  one-quarter  to  one-third  inch  long,  and  rather  resembles 
the  elm  leaf-beetle,  varying  from  pale  yellow  to  black,  with  the 
wing-covers  striped  as  shown  in  Fig.  242.  Several  wild  plants, 
including  blites,  Russian  thistle,  and  saltbusli  f  probably  furnish 
the  normal  food  of  the  insect. 

''  The  beetles  are  gregarious,  '  sometimes  occurring  in  swarms 
like  blister-beetles.'  Their  brownish-gray  eggs  are  deposited 
in  irregular  masses,  usually  on  the  under  sides  of  the  leaves. 
They  hatch  in  about  six  days,  and  their  larvae  or  young  commence 
feeding  at  once,  continuing  for  nine  or  ten  days,  when  they  dig 
their  way  into  the  ground,  a  few  days  later  coming  forth  as  beetles. 
Although  the  beetles  do  much  injury,  the  principal  damage  is 
sometimes    accomplished   by   the    larvae,    hundreds   being   found 

*  Monoxia  pvncticollis  Say.     Family  Chrysomelidoe. 
f  Dondia  americana  and  D.  depressa,  Salsola  tragus,  and  Atriplex  nrgentea. 


338       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

on  a  single  plant,  which  is  cither  consumed  or  so  injured  that  it 
shrivels  and  dies.  The  larva,  shown  in  the  illustration,  measures 
when  full  grown  about  one-third  of  an  inch  in  length.  The 
general  color  is  nearly  uniform  dark  olive  brown,  the  conspicuous 
piliferous  tubercles  being  pale  yellow,  and  the  head  and  portions 
of  the  legs  black.  The  eggs  are  dull  brownish  gray,  and  the 
surface,  as  seen  through  a  lens,  is  cov-ercd  with  septagonal  and 
hexagonal  areas."  * 


Fig.  242. — The  larger  beet  leaf-beetle  {Monoxia  pimdicollis  Say):  a,  female 
beetle;  h,  eggs;  c,  d,  larvte  from  above  and  side;  cf,  claw  of  male;  9, 
claw  of  female — all  much  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 


Control. — Paris  green  diluted  with  flour  and  dusted  over  the 
foliage  has  effectiveh'  controlled  the  pest,  and  prol^ably  any 
thorough  application  of  any  arsenical  either  wet  or  dry  would 
be  effective.  Professor  C.  P.  Gillette f  has  observed  that  the  beetles 
accumulate  on  the  "  mother  "  beets  early  in  the  spring,  so  that 
if  a  few  beets  were  left  in  the  ground  over  winter  they  might 
serve  as  trap  plants  for  the  protection  of  the  younger  plants  in 

*  Quoted  from  F.  H.  Chittenden,  Bulletin  43,  Bureau  Ent.,  U.  S.  Depf 
Agr.,  p.  10. 

tC.  P.  Gillette,  24th  Report  Colo.  Agr.  Exp.  Sta.  (1902),  pp.  108-111. 


INSECTS   INJURIOUS    TO   BEETS  AND  SPINACH 


339 


spring.     As  injury  is  mostly  on  or  near  alkali  ground,  such  soil 
should  be  avoided. 

Plant-bugs 

The  Tarnished  Plant-bug  {Lygus  pratensis — sec  page  404), 
False  Chinch-bug  (Nysius  angustatus),  and  several  of  the  com- 
mon plant-bugs  often  become  so  numerous  as  to  do  considerable 
damage  to  beets.  When  present  in  large  numbers,  a  spray  of 
kerosene  enuilsion  might  be  used  to  advantage.  Experiments 
in  New  York  show  that  the  tarnished  plant-bug  can  be  driven 
from  a  field  in'  dusting  the  rows  with  wood-ashes,  being  careful 


Fig.  243- — The  false  chinch-bug  (Nysius  angustatus) .     (After  Riley.) 

to  work  on  the  same  side  of  each  row  and  thus  gradually  driving 
them  into  the  field  adjoining. 


The  Beet  Leafhopper  * 

Very  serious  loss  to  the  sugar-beet  industry  has  occurred  in 
Colorado  and  Utah  from  a  condition  known  as  "  curly  leaf  " 
or  "blight."  Investigations  made  by  Professor  E.  D.  Ball  have 
shown  that  the  "curly  leaf  "  is  undoubtedly  caused  by  the  presence 
of  immense  numbers  of  small  leaf  hoppers,  from  10  to  100  often 
being  found  on  a  plant  in  badly  infested  fields.  The  curly  leaf 
condition  does  not  seem  to  result,  however,  except  when  the  soil 
has  become  dry  and  heated,   and   where  plants  are   shaded   or 

*  Eutettix  tenella  Baker.  See  E.  D.  Ball,  Bulletin  66,  Part  IV,  Bureau 
of  Entomology,  U.  S.  Dept.  Agr. 


340        INSECT  PESTS  OF  FARM,   GARDEN   AND  ORCHARD 

irrigated  the  damage  by  the  leafhoppers  does  not  seem  to  produce 
the  same  trouble.  Similar  injury  has  been  noted  in  parts  of 
Oregon,  but  not  of  so  serious  a  nature. 

The  beet-leafhopper  is  a   pale    yellowish-green   species    (Fig, 
244),    one-eighth  to    three-sixteenths  an    inch    long,  and    when 


Fig.  244. — The  sugarbeet  leafhopper  (Eutetiix  tenella  Baker):  a,  adult;  b, 
nymph;  /,  eggs — greatly  enlarged;  g,  .sec 'ion  of  beet  stem  showing  fresh 
eggs  in  place;  h,  same  showing  eggs  ready  to  hatch;  i,  old  egg  scars  on 
beet  stems;  j,  small  leaf  of  sugar  beet  showing  characteristic  "curly- 
leaf  "  condition;  k,  enlarged  section  of  back  of  an  extreme  case  of  curly- 
leaf  showing  warty  condition  of  veins.     (After  Ball,  U.  S.  Dept.  Agr.) 

flying  appears  almost  white,  so  that  it  is  sometimes  locally  called 
the  "  white  fly." 

Life  History. — The  hibernating  habits  of  the  adults  and  their 
food-plants  in  the  spring  have  not  been  well  determined.  They 
appear  in  the  beet-fields  late  in  June  and  lay  their  eggs  in  the 
leaf-stems,  the  eggs  hatching  in  about  two  weeks.     The  young 


INSECTS  INJURIOUS  TO  BEETS  AND  SPINACH 


341 


nymphs  appear  in  July  and  are  very  active,  being  first  found  in  the 
unfolding  leaves  at  the  centre  and  later  spreading  to  all  parts 
of  the  plant.  The  nymphs  are  variously  colored,  but  the  com- 
monest form  is  a  pale  creamy  color  with  a  brown  saddle  on  the 
middle  of  the  abdomen  and  various  mottlings  on  the  prothorax 
and  wingpads.     The  nymphs  become  "full  grown  in  from  sixteen 


Fig.  245. — ''  Hopperette  "  designed  for  collecting  leafhoppers.     (After  G.  C. 
Davis,  Mich.  Agr.  Exp.  Sta.) 


to  twenty-two  days  and  the  adults  again  become  abundant 
in  August  and  September;  they  evidently  hibernate  as  adults, 
as  no  more  eggs  are  laid  in  the  fall  as  far  as  observed. 

The  characteristics  of  the  ''  curly  leaf  "  are  described  by  Dr. 
Ball  as  follows :  ''  The  first  symptom  of  '  curly-leaf  '  or  '  blight ' 
of  the  beet  is  a  thickening  of  all  the  smaller  veinlets  of  the  leaf, 


342        INSECT  PESTS  OF  FARM,  GARDEN   AND   ORCHARD 

giving  it  a  roughened  appearance  on  the  under  nide.  This  is 
followed  by  a  curling  of  the  edge  and  a  final  rolling  up  of  the  leaf, 
the  upper  surface  always  Ix'ing  rolled  in.  As  this  progresses  the 
smaller  veinlets  grow  still  larger  and  more  irregular,  knotlike 
swellings  appear  at  frequent  intervals,  and  in  extreme  cases 
little  nipple-like  swellings  appear,  extending  to  a  height  of  nearly 
one-fourth  of  an  inch.  This  will  be  noticed  first  on  a  medium- 
sized  leaf,  gradually  spreading  to  the  younger  ones,  while  at  the 
same  time  the  beet  almost  stops  growing  and  a  large  number  of 
fibrous  roots  are  sent  out.  .  .  .  The  beet  often  continues  in  this 
way  throughout  the  season;  in  bad  cases  it  shrivels  and  dies, 
while  in  a  few  instances  there  is  a  partial  recovery  and  a  new  set 
of  leaves,  though  the  sugar  content  remains  very  low." 

Control.^ — Practical  measures  of  'control  do  not  seem  to  have 
been  very  thoroughly  tested.  With  a  better  knowledge  of  the 
hibernating  habits  of  the  species,  it  may  be  possible  to  reduce  its 
numbers  at  that  time.  After  the  hoppers  have  appeared  in 
numbers  they  must  be  dealt  with  promptl}'.  "  A  thorough 
spraying  with  kerosene  emulsion  at  a  strength  of  1  part  of  the 
stock  solution  to  5  parts  of  water,  would  destroy  most  of  the 
insects  that  it  hit,  and  by  using  a  drag  in  front  of  the  nozzles  to 
turn  the  leaves  over  and  cause  the  insects  to  jump,  most  of  them 
would  be  reached."  This  would  probably  need  to  be  repeated 
in  about  ten  days.  Hopperclozers  have  often  been  successfully 
used  for  collecting  various  forms  of  leafhoppers.  A  modifica- 
tion of  the  form  used  against  grasshoppers  (see  page  108),  with 
a  couple  of  wings  extending  out  on  either  side  of  the  row  and 
covered  with  a  sticky  substance  such  as  "  tanglefoot  "  or  that 
described  on  page  523,  would  undoubtedly  prove  effective  in 
collecting  the  adults,  particularly  before  the  females  have  laid 
their  eggs,  when  they  are  more  readily  caught.  A  "  hopperette  " 
designed  by  Professor  G.  C.  Davis  for  use  against  leafhoppers  on 
celery  in  Michigan,  is  shown  in  Fig.  245,  and  may  be  readily 
attached  to  the  frame  of  a  wheel  hoe.  The  string  across  the 
notch  at  A  strikes  the  plants  and  causes  the  hoppers  to  jump 
at  the  right  time.     By  adding  high  wide  wings  to  either  side  of 


INSECTS   INJURIOUS  TO  BEETS  AND  SPINACH 


343 


this   niacliiiic   it    should   Ix'   well   achiptcd   for   Ikh^Is   and   similar 
crops. 

Blister-beetles  * 

Among  those  insects  attacking  the  }'oung  sugar-beets  and 
often  doing  considerable  damage  after  they  have  l)ecome  partly 
grown,  few  are  more  widespread  or  do  more  general  injury  than 
the  blister-beetles.  They  have  been  especially  destructive 
in  the  northern  Mississippi  ^'alley,  where  the}^  are  usually  worst 
after  a  period  of  unusual  abundance  of  grasshoppers.  Coming 
suddenly  in  a  large  swarm,  they  settle  in  a  field  and  thoroughly 


Fig.  246. — The  striped  blister-beetle  (Epicauta  vitlata):  a,  female  beetle; 
b,  eggs;  c,  triungiilin  larva;  d,  second  or  caraboid  stage;  e,  same  as/ 
doubled  uji  as  in  i:)od;  /,  scarabseoid  stage;  g,  coarctate  larva — all  except 
e  enlarged.     (After  Riley  and  Chittenden,  U.  S.  Dept.  Agr.) 

riddle  the  foliage  with  holes  or  sti'ip  it  bare  ])efore  going  to  another 
field. 

One  of  the  most  common  forms  is  the  striped  lolister-beetle, 
or  "  old-fashioned  potato-bug  "  (Epicauta  viitata),  which  is 
shown  in  the  illustration,  together  with  the  immature  stages. 
The  ash-gray  blister-beetle  (Macrobasis  unicolor)  is  also  a  common 
form,  shown  in  Fig.  230.  Three  or  four  other  forms  are  common 
throughout  the  country,  but  are  especially  numerous  in  the  West, 
where  grasshoppers  are  more  abundant.  The  reason  for  this  is 
apparent  when  we  come  to  consider  the  life  history  of  the  pest, 
for  the  blister-beetles  are  not  an  unmixed  evil. 


*  Family  Mcloidw. 


344        INSECT  PESTS   OF  FARM,  GARDEN  AND  ORCHARD 


Life  History. — In  a  small  cavit}'  in  the  earth  the  female  beetle 
lays  some  four  or  five  hundred  eggs,  these  being  deposited  from 
July  to  October.  About  ten  days  later  the  eggs  hatch,  and 
from  them  emerge  some  small  but  very  active  larvae,  with  long 
legs,  large  heads,  and  strong  jaws. 

They  at  once  commence  running  about  in  search  of  the  pod- 
like masses  of  grasshoppers'  eggs,  and  as  soon  as  one  is  found  the 
larva  enters  it  and  commences  a  hearty  meal.  As  soon  as  his 
appetite  has  been  somewhat  satisfied  he  sheds  his  skin,  and  now 

Ijeing  surrounded  by  food  and  no  lon- 
ger needing  his  long  running  legs,  they 
are  changed  for  very  short,  aliorted 
legs,  and  the  larva  is  soft  and  sluggish. 
In  another  week  a  second  molt  takes 
place,  after  which  the  legs  and  even 
the  mouth-parts  are  still  more  atro- 
phied. After  another  molt  and  after 
consuming  all  the  eggs  in  the  pod,  the 
larva  now  goes  deeper  in  the  soil,  and 
inside  a  small  oval  cavity  again  sheds 
its  skin,  and  hibernates  over  winter  as 
a  sort  of  semipupa.  In  the  spring  the 
larva  appears  again  much  like  the 
second  stage,  but  does  not  eat  much, 
and  soon  goes  into  the  pupal  stage,  from  which  emerges  the  adidt 
beetle.  Altogether  the  life  history  is  one  of  the  most  peculiar  and 
complicated  among  insects.  Thus  the  blister-beetles  are  one  of  the 
most  important  factors  in  holding  the  grasshoppers  in  check. 

Remedies. — However,  when  they  swarm  into  the  beet-fields, 
potato-  or  garden-patches,  one  cannot  afford  to  allow  them  to 
consume  one  crop  for  the  good  they  may  do  in  saving  another 
from  still  another  insect  scourge.  ''  A  bird  in  the  hand  is  worth 
two  in  the  bush,"  is  equally  true  of  insects.  So  be  ready  for  them 
on  their  first  appearance ;  give  the  plants  a  thorough  spraying 
with  of  1  pound  of  Paris  green,  and  1  pound  of  lime  to  125  gallons 
of  water.      It  may    be  well   to  spray  with  Bordeaux  mixture, 


Fig.  247.-  The  black  blister 
beetle  {Epicauta  pennsyl- 
vanica).  (After  Chitten- 
den, U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO    BEETS  AND  SPINACH  345 

which  will  prevent  various  fungous  diseases,  and  with  which 
Paris  green  can  be  used  much  stronger  without  danger  of  burn- 
ing the  foliage;  or  it  may  be  applied  dry  In'  mixing  with  from 
ten  to  twenty  parts  of  flour  or  plaster,  dusting  it  on  in  early 
morning,  while  the  dew  is  still  on  the  plants.  Arsenate  of 
lead  sprayed  at  the  rate  of  3  pounds  to  50  gallons,  or  used  as 
a  dust,  will  be  equally  effective,  will  adhere  to  the  foliage  better, 
and  will  be  less  likely  to  burn  the  fohage. 

The  Beet  or  Spinach  Leaf-miner.* 

Frequently  beet  and  spinach  leaves  will  be  found  with  tor- 
tuous mines  or  large  blotches  which  have  been  mined  out  by 
small  white  maggots  beneath  the  surface  epidermis.  This  injury 
is  most  commonly  due  to  the  maggot  of  a  small  fly  shown  in 
Fig.  248.  "The  ground  color  is  gray  with  the  front  of  the  head 
silver  white.  The  body,  including  the  legs,  is  somewhat  sparsely 
covered  with  rather  long  stiff  black  hairs.  When  in  action  the 
body  is  usually  carried  in  a  somewhat  curved  position,  but  when 
extended  measures  nearly  a  quarter  of  an  inch.  The  maggot 
(/)  is  white,  and  so  nearly  transparent  that  the  contents  of  the 
abdomen  can  be  seen  through  the  posterior  portion." 

Life  History. — "  The  flies,  by  close  observation,  may  be  seen 
in  flight  just  above  the  ground  or  hovering  about  their  different 
food  plants.  The  eggs  are  placed  on  the  lower  surface  of  the 
leaves  and  arranged  in  masses  of  from  two  to  five.  When  the 
young  hatch  they  bury  themselves  within  the  leaf  tissue,  con- 
structing a  thread-like  mine  which  they  afterwards  extend  in  a 
curve  or  semicircle.  Transformation  to  pupae  takes  place  in 
most  cases  in  loose  soil,  which  the  maggots  enter  to  only  a  short 
distance,  or  under  fallen  leaves.  Occasionally  maggots  trans- 
form within  a  leaf  if  the  latter  happens  to  rest  on  the  ground. 
Dr.  Howard  states  that  the  eggs  hatch  in  from  three  to  four 
days,  and  the  larval  stage  is  passed  in  seven  or  eight  days,  the 
puparium  or  resting  stage  requiring  from  ten  to  twenty  days. 

*  Pegomyia  vicina  Lintn.  See  Chittenden,  I.e.,  from  which  the  quota- 
tions are  taken. 


346        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

"  Injury  appears  to  be  most  frequent  in  late  fall,  but 
may  be  due  to  earlier  generations  in  midsummer.  "  In  many 
eases  infestation  can  be  traced  directly  to  the  insect  having 
bred  in  lambsquarters  and  similar  weeds,  which  if  -not  destroyed 
by  ordinary  methods  of  cultivation  mature  and  die  during 
October." 

Control. — Where  this  pest  occurs  in  small  gardens  it  may  be 
controlled  by  picking  and  destroying  the  infested  leaves,   and 


Fig.  248. — The  beet  leaf-miner  {Pegomyia  vicina  Lintn.):  a,  fly;  h,  head  of; 
male  fly;  c,  head  of  female;  d,  surface  of  egg  highly  magnified;  e,  egg 
/,  maggot;  g,  head  of  same;  ./,  anal  segment;  k,  anal  spiracles — all 
enlarged.      (After  Howard,  U.  S.  Dept.  Agr.) 


even  in  larger  fields  such  a  practice  might  prevent  its  mcrease 
and  consequent  injury.  Those  insecticides  which  have  been 
tried  as  remedies  seem  to  have  had  no  effect.  Deep  plowing 
and  thorough  harrowing  of  infested  fields  as  soon  as  the  crop  can 
be  removed  shoukl  greatly  lessen  injury  the  next  year.  As  this 
species  seems  to  prefer  spinach  to  beet.  Dr.  Chittenden  has 
suggested  that  spinach  might  be  used  as  a  trap  crop  in  large 
fields  of  sugar  beets  where  the  injury  warranted  such  a  measure. 


CHAPTER  XVIII 
INSECTS  INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS  * 

The  Cabbage  Maggot  f 

Throughout  the  Middle  and  Xorthcrn  States  the  cabbage  mag- 
got is  one  of  the  most  destructive  and  most  difficult  to  combat  of 
all  the  insects  affecting  cabbage,  cauliflower  and  radishes.  Just 
as  the  plants  are  commencing  to  make  a  good  growth  they  sud- 
denly appear  sick,  many  are  found  wilting,  and  soon  die.  Exami- 
nation of  the  roots  shows  that  they  have  been  riddled  by  small, 
white  maggots  as  shown  in  Fig.  254.  Early-planted  cabbage, 
cauliflower  and  radishes  are  particularly  affected,  and  later  in  the 
season  the  maggots  will  be  found  on  turnips  and  wild  mustard. 

These  maggots  are  the  larvae  of  a  small  fly,  resembling  the 
house-fly,  but  distinctly  smaller,  being  only  three-sixteenths 
inch  long,  with  a  narrower  body  and  proportionately  larger  wings. 
It  is  a  grayish  color  with  three  dark  stripes  on  the  thorax  and  one 
along  the  middle  of  the  abdomen,  and  the  body  bears  numerous 
stiff  hairs  or  bristles.  The  flies  appear  just  as  early  cabbage  is  set 
out,  in  late  April  and  early  May  in  New  Jersey,  and  in  late  Mav  in 
southern  Minnesota.  They  do  not  fly  far  and  seem  to  avoid  fields 
which  are  swept  by  the  wind. 

Life  History. — The  females  deposit  their  eggs  on  the  stem  of 
the  plant  or  in  the  soil  near  the  stem,  at  or  just  beneath  the  surface 

*  See  Carman,  "Insects  Injurious  to  Cabbage,"  Bulletin  11-i,  Ky.  Agr. 
Exp.  St  a. 

'\  Pegomyia  brassicoe  Bouche.  Family  A ntho mi jii doc.  See  Slingerland, 
Bulletin  78,  Cornell  Univ.  Agr.  Exp.  Sta.;  J.  B.  Smith,  Bulletin  200,  N.  J. 
Agr.  Exp.  Sta.;  F.  H.  Chittenden,  Circular  63,  Bureau  of  Ent.,  U.  S.  Dept. 
Agr.;  F.  L.  Washburn,  11th  and  12th  Reports  State  Ent.  of  Minn.;  W.  J. 
Schoene,  Bulletins  301  and  334,  N.  Y.  Agr.  Exp.  Sta.,  Journal  of  Economic 
Entomology,  Vol.  IV,  p.  210. 

347 


348      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

of  the  soil,  each  female  laying  some  fifty  eggs.  The  eggs  are  most 
abundant  in  late  May  and  early  June  in  central  New  York.  Usu- 
ally a  female  lays  but  one  or  two  eggs  on  a  plant  and  prefers  to  lay 
them  in  a  crevice  of  the  stem  or  very  near  it,  for  if  the  3"oung  mag- 
gots have  to  travel  far  to  reach  their  food,  many  will  die  before  find- 
ing it,  and  if  laid  on  hard  soil  the  maggots  will  be  imable  to  pene- 
trate it  to  the  soft  tissue  of  the  root,  as  they  are  unable  to  feed  on 


Fig.  249.— Cabbage  root  infested  with  maggots.     (After  Slingerland.) 

the  hard  stem  above  ground.  The  eggs  are  about  .one  twenty- 
fifth  inch  long,  of  a  pure  white  color,  which  i-enders  them 
easily  seen  against  the  soil  by  one  familiar  with  them,  and  are  of  the 
shape  shown  in  Fig.  251,  having  a  curious  ridge  along  one  side.  The 
eggs  hatch  in  from  three  to  ten  days,  averaging  five  to  seven. 
The  little  maggots  at  once  commence  rasping  the  surface  of  the 
tender  roots,  gradually  mine  into  them,  and  in  three  or  four  weeks 
have  become  full  grown.      The  grown  maggot  is  one-third  inch 


INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS   CROPS      349 

long,  white  or  yellowish  in  color,  tapering  toward  the  head  and 
obliquely  truncate  at  the  tip  of  the  abdomen.  From  the  head  a 
pair  of  strong,  black,  hook-like,  rasping  jaws  project  downward, 
antl  just  back  of  the  head  on  either  side  is  a  minute,  light  brown, 
fan-like  projection  (Fig.  253,  h),  or  spiracle,  which  leads  into  the 
breathing  system.     The  oblique  posterior  end  is  surrounded  by 


Fig.  250. — The  cabbage  maggot  fly   {Pegomyia  hrassiccB  Bouch^),   female 
greatly  enlarged.     (After  Slingerland.) 


twelve  rounded  tubercles  and  in  the  centre  are  two  brownish  spira- 
cles (Fig.  253,  a).  When  done  feeding  the  larva  burrows  one-half 
to  one  inch  under  the  surface  of  the  soil,  and  the  outerskin  gradually 
hardens  until  it  forms  a  firm  brown  shell,  called  a  puparium, 
within  which  the  larva  transforms  to  a  true  pupa.  Frequently  the 
puparia  are  found  in  the  galleries  made  by  the  maggot  or  in  crevices 
of  the  roots.  During  the  summer  this  stage  lasts  about  two  weeks, 
but  in  the  fall  most  of  the  insects  remain  in  this  condition  over  win- 


350        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


tcr.  Tims  the  whole  life  cycle  from  ciij^  to  adult  ivquires  al)out  six 
to  ten  or  twelve  weeks,  according  to  the  temperature  and  moisture, 
and  the  second  generation  of  flies  appear  in  June  in  New  Jersey  or 
by  mid-July  in  southern  Minnesota.  The  maggots  of  the  second 
generation  seem  to  do  but  little  damage.  The  life  history  of  the 
insect  during  late  summer  has  not  been  satisfac- 
torily determined,  but  there  is  undoubtedly  a  third 
generation  and  in  the  South,  possibly  a  fourth,  the 
work  of  the  last  generation  being  sometimes 
noticed  in  late  cabbage  in  early  fall.  On  Long 
Island,  N.  Y.,  the  larvas  have  been  observed  as 
abundant  upon  cabbage  stumps  in  Septeml)er  and 
October,  working  above  ground,  and  the  adults 
and  eggs  have  been  common  around  the  ad- 
ventitious buds.  Rough  estimates  indicate  300 
to  1500  maggots  per  acre  on  these  stumps.  The 
puparia  of  the  last,  and  in  the  North  possibly 
some  of  those  of  the  second  generation,  remain 
in  the  soil  over  winter,  though  there  is  some  evi- 
dencethat  the  flies  may  also  hibernate  in  the 
Middle  States. 

Control. — The  most  effective  measures  of  control  consist  in  cul- 
tural methods  and  preventives,  but  little  practical  success  having 
attended  the  use  of  remedies  to  kill  the  maggots. 

Cultural  Methods. — Inasmuch  as  the  puparia  remain  in  the  soil 
or  in  the  old  roots  or  stumps  over  winter,  it  is  important  for  this  as 
well  as  other  cabbage  pests  to  gather  and  destroy  all  the  refuse  of  the 
crop  as  soon  as  possible  and  then  plow  infested  land  thoroughly  in 
the  fall.  Mr.  Schoene  has  shown  that  by  plowing  badly  infested 
seed-beds  six  or  seven  inches  deep  that  only  one-fourth  as  many  flies 
emerged  as  where  the  soil  was  undisturbed.  A  rotation  of  the  crop 
will  be  of  value  where  cabbages  are  not  grown  on  large  acreages. 
Cabbage  and  other  cruciferous  crops  should  not  be  planted  after 
each  other,  as  all  are  affected  by  the  same  pests.  It  is  evident  that 
if  the  crop  is  planted  at  some  distance  from  that  of  the  previous 
year,   and    as  the  flies   are    known  to  avoid  wind-swept   fields, 


Fig.  251. -Egg 
of  cabbage 
maggot, 
greatly  en- 
larged ;  hair 
lineat  center 
of  h  shows 
natural  size; 
h,  outline  of 
side  view. — 
(After  Shng- 
erland). 


INJURIOUS  TO   CABBAGE   AND   CRUCIFEROUS   CROPS      351 


tluit  many  of  tliciii  will  not  succeed   in  finding  the  new  plant- 
ing. 

As  the  maggots  infest  wild  mustard  and  various  similar  weeds, 
they  should  be  destroyed  as  far  as  possible  and  crops  affected  by 
the  maggots  should  not  be  planted  on  or  near  land  Imdly  infested 
with  such  weeds  if  avoidable.  Wild  mustard  may  be  readily  killed 
by  spraying  it  while  young  with  iron  sulfate,  2  pounds  to  1 
gallon  of  water. 

Late-planted  caljbage  is 
but  slightly  affected  as  com- 
pared with  that  planted  earlier. 
The  earliest  radishes  are  often 
cpite  free  from  the  pest,  those 
planted  later  and  maturing 
just  as  the  flies  are  abundant 
are  badly  injured,  and  the  later 
plantings  are  free  from  injury. 
It  is  evident,  therefore,  that 
where  planting  of  the  main 
crop  can  be  delayed 
most  of  the  flies 
posited,     that     it     will     escape 

serious      injury.       Furthermore,  „      „,..,     ^        ,     , , 

,,  -       '  ...       tiG.  252. — Eggs  of  cabbage  maggot  at 

either       cabbage        or       radishes     base  of  stalk.     (Photo  by  Headlee.) 

may  be    used    as    a    trap    crop, 

by  planting  a  few  rows  early  and  as  soon  as  the  flies  had  laid 

their  eggson  them,  plowing  them  under  deeply  and  then  setting 

the   main   crop.      All   of   these    methods    involve    a    familiarity 

with   the   fly   and   its  eggs  which    any   observant    grower   may 

soon  acquire. 

High  fertilization  with  a  quickly  available  fertilizer  will  enable 
the  plants  to  make  a  rapid  growth  and  will  be  profitable  even  if 
maggots  do  not  occur. 

Thorough  and  frequent  cultivation  while  the  eggs  are  being 
laid  destroys  many  of  them.  Indeed,  one  of  the  best  means 
of  control,  which  is  extensively  practiced  by  many  growers,  is  to 


until  after  !^%0v'ft'  -V  '^ 
have  ovi-  p.^>F'Jt>V:  ^^ 
ill     escape     l^\f'\>,U^\  ^.r.^>': 


352         INSECT   PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


'St 

ar  ^ 

a 

Fig.  253. — Cabbage  maggot,  side 
view,  enlarged,  hair  line  repre- 
sents natural  size;  a,  view  of 
caudal  segment;  b,  outline  of 
spiracle  back  of  head — greatly 
enlarged.    (After  Slingerland.) 


hill  up  the  earth  around  the  young  plants  when  set,  and  as  soon  as 
eggs  are  laid,  pull  the  soil  containing  the  eggs  away  from  the  plant 
into  the  middle  of  the  row,  where  they  or  the  maggots  hatching 
from  them  will  be  killed  by  the  heat.     This  involves  considerable 

hand  work,   but  where  carefully 
and  intelligently  followed   is  one 
of  the  surest  means  of  control. 
Preventives. — Where  late  cab- 
^  _  ,.  u       -^        bage  is  grown   the  plants  often 

^«i/'  '^  become    infested    in    the    seed- 

bed. To  avoid  this  the  seed- 
beds should  be  covered  with 
cheesecloth.  The  sides  of  the 
frame  are  made  of  12-inch  boards, 
across  which  wires  are  stretched 
to  prevent  sagging  of  the  cloth, 
as  the  whole  must  be  fly-tight.  The  cover  should  be  removed 
a  week  or  ten  days  before  transplanting,  so  that  the  plants  may 
harden.  If  eggs  are  observed  in  the  seed-bed  during  this  time, 
transplant  at  once. 

The  most  successful  preventive  yet  used  consists  of  a  tarred 
felt  card  placed  around  each  plant  so  as  to  form  a  collar,  lying 
upon  the  surface  of  the  soil  and  thus  preventing  the  fly  from 
depositing  her  eggs.  These  cards  were  originally  devised  by 
Professor  W.  H.  Goff,  of  Wisconsin,  and  have  been  extensively 
used  by  large  growers  in  that  State  for  many  years,  as  well  as 
in  New  York,  and  recent  'experiments  in  New  Jersey  and 
Minnesota  have  proven  them  very  satisfactory.  The  cards 
should  be  made  of  one-ply  tarred  felt,  as  ordinary  tarred  paper 
or  building  paper  curls  up  and  is  not  as  effective.  The  cardo 
are  made  in  a  hexagonal  shape,  with  a  slit  extending  from  one 
corner  to  the  centre,  which  is  slit  with  a  star-shaped  cut  to 
accommodate  the  stem.  The  cards  are  cut  with  a  tool  shown 
in  Fig.  255,  which  may  be  made  by  any  blacksmith,  and  are 
cut  out  in  rows  as  illustrated,  one  cut  of  the  tool  making 
a  card.     The  cards  should  be  placed  around  the  plants  when 


INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS      353 

they  arc  set.  The  earth  should  ])c  smoothed  down  and  well 
firmed  by  the  hand,  the  card  then  applied  to  the  plant,  and 
pressed  down  tight  to  the  ground,  so  that  it  fits  snugly  around 
the  stem  and  the  edges  of  the  slit  meet.  With  a  little  experience 
the  cards  may  be  applied  rapidly ,  and  though  involving  con- 
siderable handwork,  the  testimony  of  those  who  have  used 
them  for  many  years  shows  that  the  method  is  entirely  practical 
and  is  to  be  preferred  to  doul)tful  remedies. 


Fig.  254. — Cabbage  roots  destroyed  by  the  cabbage  maggot.    (After 
Slingerland.) 

A  mixture  of  lime  and  carbolic  acid  has  recently  been 
used  by  applying  it  to  the  surface  of  the  soil  around  the 
plants,  so  as  to  form  a  slight  crust,  the  carbolic  acid  acting  pos- 
sibly as  a  repellant.  The  lime  is  slaked  to  a  thin  cream,  and 
diluted  to  3  pints  to  a  gallon  of  water,  to  which  is  added  a 
tablespoonful  of  crude  carbolic  acid.  It  is  applied  liberally  to 
the  soil  immediately  around  the  plants  with  a  sprinkling  can. 
This  has  proven  quite  effective  for  cabbage  in  New  Jersey, 
but  in  Minnesota  cabbage  so  treated  showed  but  little  benefit, 
though  radishes  were  somewhat  protected.  Kerosene  and  sand, 
gas  tar  and    sand,    tobacco    dust    and  many   other   substances 


354         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


have  been  used  to  place  around  the  plant  and  act  as  repel- 
lants  or  preventives,  but  all  have  some  objection  or  have  not 
been  sufficiently  tested  to  show  their  effectiveness  and  practica- 
bility. Dr.  J.  B.  Smith  reports,  however,  that  cauliflower-growers 
at  Richfield,  N.  J.,  have  been  using  gas  tar,  1  part  to  25  parts  of 
sand,  for  several  years  with  good  results.  The  gas  tar  costs  $1.25 
a  gallon  and  will  treat  1000  plants.  A  greater  proportion  of  gas 
tar  has  proven  injurious. 

Remedies. — For  the  destruction  of  the  maggots,  both  carbolic 

acid  emulsion  and  hellebore 
decoction  have  been  exten- 
sively used  with  varying  re- 
sults, but  from  the  evidence 
so  far  submitted,  the  grower 
would  hardly  seem  war- 
ranted in  placing  much  de- 
pendence upon  them,  though 
whei-e  preventive  measures 
have  been  neglected,  they 
may  aid  in  reducing  the 
numl^er  of  maggots  and  pre- 
vent a  total  loss.  To  make 
the  emulsion,  dissolve  1 
pound  of  soap  in  a  gallon  of 
boiling  water ;  to  this  add  1 
pint  of  crude  carbolic  acid 
and  churn  thoroughly  until 
a  good  creamy  emulsion  is  made.  For  use,  dilute  one  part  of 
the  emulsion  with  30  parts  of  water  and  apply  4  to  6  ounces 
to  each  plant.  It  may  be  conveniently  applied  with  a  watering 
pot.  The  earth  should  be  pulled  away  from  the  plants  so  that 
the  emulsion  may  be  brought  into  actual  contact  with  the 
larvie  on  the  roots.  Application  should  be  commenced  as  soon 
as  maggots  are  observed,  repeated  in  4  or  5  days,  and  then 
once  a  week  for  a  month.  Well-grown  maggots  are  quite  resistant 
to  the  emulsion,  but  it  will  destroy  the  young  as  they  hatch  before 


Fig.  255. — n,  tarred  felt  card  in  outline 
one-thirtl  size;  /),  tool  for  cutting 
cards,  about  one-sixth  size;  c,  show- 
ing how  tool  is  used,  dotted  line 
indicating  position  of  edge  of  tool. 
(After  GofT.) 


INJURIOUS  TO    CABBAGE  AND   CRUCIFEROUS  CROPS     355 

they  become  established  in  the  root.  Hellebore  decoction  is  made 
by  steeping  2  ounces  of  jiowtlered  hellebore  in  a  ({uart  of  boiling 
water  for  half  an  hour,  and  then  diluting  to  make  a  gallon  of  liquid. 
It  may  be  kept  in  the  concentrated  foi'm,  but  should  be  thoroughly 
stirred  before  using.  It  is  applied  in  the  same  manner  as  the  car- 
bolic emulsion.  Both  these  mixtures  may  also  be  used  against 
maggots  on  radishes  and  onions  by  making  thorough  applications 
along  the  rows. 

The  surest  method  of  destroying  the  maggots  on  the  roots  is  by 
the  use  of  carbon  bisulfide  (see  page  57) .  This  is  entirely  practi- 
cable on  a  few  plants,  but  has  not  come  into  general  use  on  a  large 
scale,  as  no  satisfactory  tool  for  its  injection  into  the  soil  is  avail- 
able. A  small  hole  should  be  made  with  a  dibble  4  to  6  inches  from 
the  infested  stem,  and  a  teaspoonful  of  carbon  bisulfide  injected  and 
the  hole  tightly  closed  with  earth.  If  made'  too  close  to  the  plant 
the  roots  will  be  injured.  The  fumes  kill  the  maggots  by  permeat- 
ing the  soil.  Adhere  plants  are  badly  infested  injection  on  two 
sides  may  be  necessary.  The  material  will  cost  about  $1.00  per 
1000  plants.  Professor  Slingerland  describes  an  injector,  no 
longer  made,  but  similar  tools  are  for  sale  by  dealers  in  agricul- 
tural implements  in  France,  and  might  be  made  by  an}-  machinist. 

The  Imported  Cabbage  Worm  * 

Probably  the  worst  pest  of  the  cabljage  and  one  of  the  best- 
known  garden  insects  is  the  common  cabbage  worm,  whose  parent 
is  the  common  white  butterfly.  It  is  an  old  European  pest  and 
was  imported  near  Quebec,  Canada,  about  1860,  whence  it  spread 
to  New  England,  reached  New  York  in  1S6S,  Cleveland,  Ohio,  by 
1875,  and  the  Gulf  States  by  1880,  and  has  since  spread  to  all  parts 
of  the  country. 

The  butterfhes  are  among  the  first  to  emerge  in  early  spring. 
They  are  white,  marked  with  black  near  the  tip  of  the  fore-wings, 
which  expand  nearly  2  inches.     The  female  bears  two  black  spots 

*  Pontia  rapoe  Linn.  Family  Pieridoe.  See  F.  H.  Chittenden,  Circular  60, 
Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


356 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


on  each  fore-wing,  while  the  male  has  only  one,  and  both  sexes  have 
a  black  spot  on  the  anterior  margin  of  the  hind-wings. 


Fig.  256. — ^The  cabbage  butterfly  (Pontia  rapce  Linn.):  "  larva;  b,  chrysali.s; 
c,  male  butterfly;   d,  female  butterfly.     (After  C.  M.  Weed.) 

Life  History. — The  butterflies  soon  commence  to  lay  their  eggs 
on  whatever  food-plant  is  available.     The  larvae  feed  on  all  of  the 


INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS       357 


common  cultivated  crucifers  as  well  as  man}'  wild  sorts,  so  that  the 
species  is  never  without  food.  The  small  yellowish,  oval  eggs  are 
laid  on  end  on  the  foliage,  and  are  marked  with  prominent  longi- 
tudinal ridges.  They  hatch  in  from  four  to  eight  days.  The  larvae 
grow  very  rapidly,  gorging  themselves  on  the  foliage,  which  they 
skeletonize  in  their  well-known  manner,  and  become  full  grown  in 
from  ten  days  to  two  weeks.  The  mature  cabbage  worm  is  about 
1^  inches  long,  of  a  velvety  green  color,  very  similar  to  the  foliage, 
with  a  faint  }-ellow  stripe  down  the  middle  of  the  back  and  a  row 
of  yellow  spots  one  each  side.  The  surface,  when  seen  under  a 
lens,  is  finely  roughened  and  dotted  with  small  l)lack  specks.     The 


Fig.  257. —Pteromal us  puparum,  a  chalcis-fly  which  parasitizes  the  cabbage 
worm  and  many  other  injurious  insects,male  and  femalegreatlyenlarged — 
hair  hne  shows  natural  size.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

chrysalis  is  attached  to  the  foliage  by  a  strand  of  silk  around  the 
thorax  and  is  first  greenish  and  later  light  brown  in  color.  The 
butterflies  emerge  in  from  one  to  two  weeks  in  the  summer,  but 
the  chrysalides  of  the  last  generation  in  fall  hibernate  over  winter 
among  the  old  stalks  and  rubbish  on  the  fields.  •  Thus  the  whole 
Ufe  cycle  in  summer  requires  from  three  to  five  weeks.  In  New 
England  there  are  three  generations  a  season  and  there  are  prob- 
ably five  or  six  in  the  extreme  south,  as  the  butterflies  there  remain 
on  the  wing  all  winter. 

Eyiemies. — Fortunately,  the  parasites  of  the  cabbage  worm  are 
becoming  very  effective  in  checking  its  multiplication,  and  in 
many  sections  of  Xew  England  where  it  has  existed  the  longest, 
it  rarely  becomes  very  injurious,  so  well  do  the  parasites  control 


358         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

it.  Most  of  these  are  importations  from  Europe,  one  of  the 
most  important  being  a  small  wasp-like  Braconid  fly  (Apanteles 
glomeratus  Linn.)  which  was  purposely  imported  from  England 
in  1883.  During  the  autumn  of  1904  Dr.  Chittenden  states  that 
it  killed  practically  every  worm  at  Washington,  D.  C.  The  maggots 
of  these  little  parasites  live  within  the  worms  and  when  full  grown 
come  forth  and  spin  masses  of  small  white  cocoons  on  the  foliage, 
often  attached  to  the  dead  or  dying  worm  (Fig.  167).  Another 
very   important   parasite    is    a    minute   Chalcis-fly    (Pteronialus 


Fig.  258. — Apanteles  glomeratus,  a  parasite  of  the  cabbage  worm:  a,  adult 
fly;  h,  cocoon;  c,  flies  escaping  from  cocoons — natural  size,  a,  b,  highly 
magnified.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

puparum  Linn.),  about  one-sixteenth  of  an  inch  long,  which  was 
probably  imported  with  its  host.  These  often  emerge  in  immense 
numbers,  hundreds  of  them  often  being  secured  from  a  single 
worm.  Wasps  frequently  prey  on  the  caterpillars,  using  them  for 
provisioning  their  nests.  Various  predaceous  bugs  also  attack 
the  worms  as  well  as  numerous  other  internal  parasites. 

Control. — As  the  chrysalids  pass  the  winter  on  the  old  stumps, 
foliage,  and  rubbish  on  the  field,  it  is  evident  that  they  should  be 
destroyed  and  the  field  plowed  as  soon  after  the  crop  is  removed 
as  possible,     A  few  stalks  may  well  be  left  standing  here  and 


INJttRiOUS   TO  CABBAGE  AND  CRUCIFEROUS  CROPS    359 

there  and  Ix'  kcjjt  well  poisoiietl,  .so  as  to  act  as  traps  to  destroy 
worms  from  eggs  laid  by  late  females. 

The  most  effective  means  of  control  is  spraying  or  dusting 
with  Paris  green  or  arsenate  of  lead.  The  former  is  used  J  pound 
to  the  barrel  and  the  latter  2  to  3  pounds  per  barrel  of  water. 
As  the  foliage  of  cabbage  is  extremely  smooth  it  will  be  advisable 
to  add  2  or  3  pounds  of  resin  soap  or  "  sticker  "  to  render  the 
material  more  adhesive  (see  page  46).  The  arsenicals  should 
be  applied  as  soon  as  the  plants  are  set,  and  they  should  be  kept 
well  covered  until  the  heads  are  half  formed.  If  this  is  done, 
the  young  larva)  will  be  destroyed  before  they  burrow  into  the 
heads,  and  there  will  be  but  little  damage  after  the  spraying  is 
stopped.  Although  there  is  some  prejudice  against  poisoning 
cabbage,  it  is  entirely  unfounded,  for  it  has  been  shown  that  a 
person  would  need  to  eat  twenty-eight  cabbages  at  once,  if  dusted 
in  the  ordinary  manner,  to  secure  poisonous  effects.  It  is  obvious 
that  plants  should  not  have  large  quantities  of  dust  placed  on 
them  after  they  commence  to  head,  and  such  apphcations  are 
entirely  unnecessary. 

Various  contact  insecticides  may  be  used  against  the  worms 
on  a  few  plants,  but  are  not  practicable  for  large  acreages.  Thus 
water  heated  to  150°  F.,  will  kill  all  the  worms  which  it  hits. 
Kerosene  emulsion  will  kill  the  larvae,  but  must  hit  them,  and 
may  leave  an  odor  on  the  plant.  Pyrethrum  or  buhach  has  been 
used  effectively,  applying  it  either  dry  or  diluted  with  flour, 
or  sprayed  as  a  decoction  at  the  rate  of  1  ounce  to  a  gallon  of 
water.  Dilute  tobacco  extract  has  also  proven  effective,  but 
all  of  these  substances  have  the  disadvantage  that  they 
must  be  brought  into  actual  contact  with  the  worms  to  kill 
them. 


360       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Southern  Cabbage  Butterfly  * 

Before  the  invasion  of  the  imported  cabbage  worm  this  species 
was  the  cause  of  considerable  injury  from  the  Middle  States 
southward,  but  it  has  now  been  largely  replaced  and  overshadowed 
in  importance  by  the  imported  species.  The  male  butterfly  is 
very  similar  in  marking  to  the  female  of  P.  rapce,  and  would  not 


Fig.  259. — The  southern  cabbage  butterfly;  a,  male;  b,  female.    (After  Riley.) 

be  distinguished  on  the  wing.  The  female  is  more  heavily 
marked  with  black,  as  shown  in  Fig.  259.  The  caterpillar  is  a 
greenish-blue  color  with  four  longitudinal,  yellow  stripes,   and 


Fig.  260. — The  southern  cabbage  butterfly :  a,  larva;  &,  pupa.     (After  Riley.) 


covered  with  Ijlack  dots.  The  habits  are  very  similar  to  those 
of  the  imported  cabbage  worm,  and  the  same  methods  of  control 
should  be  used. 

*  Pontia  protodice  Boisd.     Family  Pieridae. 


INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS       361 


The  Potherb  Butterfly  * 

This  species  is  more  common  in  the  North  and  East  and  is 

distinguished  from  its  near  rela- 
tives by  the  wings  being  uniform 
white  without  spots.  The  larvae 
are  very  similar  to  those  of  the 
imported  species  and  the  habits 
are  very  similar.  Like  the  south- 
ern species,  though  formerly  very 
common  and  often  injurious, 
this  species  is  now  rarely  com- 
mon enough  to  do  much  injury 
and  feeds  mostly  on  wild  plants. 


Fig.    261.— The  potherb   butterfly 
and  caterpillar.    (After  Harris.) 


The  same  remedies  as  for  the  imported  species  should   be   used. 

The  Cabbage  Looper  t 

Next  to  the  imported  cabbage  worm  the  looper  is  probably 
the  most  serious  pest  of  cabbage  and  closely  resembles  it  in  the 
way  it  strips  the  foliage.  The  name  "  looper  "  is  derived  from 
its  "  looping  "  habit  of  walking  like  a  measuring  worm,  due  to  the 
absence  of  legs  on  the  third  and  fourth  abdominal  segments. 
The  larvse  are  pale  to  dark  green  in  color,  marked  with  several 
longitudinal  white  lines,  as  shown  in  Fig.  262,  which  become 
obscure  as  they  become  full  grown,  so  that  they  might  be  easily 
mistaken  for  the  common  cabbage  worms  w^re  it  not  for  the  loop- 
ing gait.  The  species  occurs  throughout  the  territory  east  of  the 
Rockies,  but  is  much  more  commonly  injurious  in  the  Middle  and 
Southern  States.  Although  cabbage  and  cauliflower  are  the 
favorite  food  plants,  it  attacks  all  of  the  cruciferous  crops,  is 
frequently  injurious  to  lettuce,  peas,  celery  and  beets,  and  has 
been  found  upon  quite  a  list  of  cultivated  crops  and  various  weeds. 

*  Pontia  napi  Linn.     Family  Pieridce. 

t  Autographa  brassicoe  Riley.  Family  Noctuidce.  See  F.  H.  Chittenden, 
Bulletin  33,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.;  F.  A.  Sirrine,  Bulletin  144, 
N.  Y.  Agr.  Exp.  Sta. 


362         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Life  History. — The  life  history  has  not  been  carefully  observed, 
but  it  seems  probable  that  the  winter  is  passed  in  the  pupa  stage 
in  the  old  leaves,  stumps  and  rubbish  of  the  cabbage  field.  Sirrine 
states  that  the  life  history  is  similar  to  that  of  the  imported 
cabbage  worm,  and  it  seems  probable  that  there  are  three  genera- 
tions a  year  in  the  Middle  States,  and  possibly  more  further 
South.  Injury  to  cabbage  seems  to  be  worse  in  late  summer. 
When  full  grown  the  larva  spins  a  very  thin,  transparent,  white 


Fig.  262. — The  cabbage  looper  (Autographa  brassiccp  Riley):  a,  male  moth; 
b  egg  from  above  and  from  side;  c,  full  grown  larva  in  natural  position 
feeding;  d,  pupa  in  cocoon — a,  c,  d,  one-third  larger  than  natural  size, 
b,  more  enlarged.     (A'^ter  Howard  and  Chittenden,  U.  S.  Dept.  Agr.) 

cocoon,  attached  to  the  leaf  upon  which  it  has  been  feeding  and 
in  it  transforms  to  the  light-brown  pupa.  The  pupal  stage  varies 
from  a  week  in  midsummer  to"  three  weeks  in  October,  and  the 
pupae  of  the  last  brood  hibernate  over  winter. 

The  moth  has  a  wing  expanse  of  about  1{  inches,  and  the  fore-, 
wings  are  grayish  brown  mottled  with  gray,  whitish,  and  blackish, 
as  shown  in  Figs.  262,  263.     Just  inside  of  the  centre  of  the  fore- 
wings  is  a  characteristic  white  spot.     The  hind-wings  are  paler 


INJURIOUS    TO  CABBAGE  AND  CRUCIFEROUS  CROPS      363 

brown,  with  the  outer  border  thirker,  and  the  margins  of  Ijoth 
wings  are  strongly  scalloped. 

Control. — The  same  general  methods  as  advised  for  the  imported 
cabbage  worm  will  effect  the  control  of  this  species.  Sirrine 
states  that  dusting  the  plants  with  Paris  green  has  not  proved 
satisfactory,  but  found  the  use  of  Paris  green  with  the  resin  soap 


Fig.  263. — The  cabbage  looper  moth  at  rest  from  side  and  from  above — 
natural  size. 

sticker  (page  46)  to  be  very  effective.  Arsenate  of  lead  is  more 
adhesive  and  is  therefore  superior  for  cabbage,  but  will  be  improved 
by  the  addition  of  the  "  sticker." 

The  Cross-striped  Cabbage  Worm  * 
Throughout   the   Southeastern   and    (lulf    States    the     cater- 
pillar of  a  native  moth,  known  as  tlu^  Cross-striped  Cabbage  Worm, 


*  Evergpstis  rimosalis  (iuen.     Family  Pyralidcr. 
Bulletin  33,  n.  s.,  Div.  Eut.,  U.  S.  Dept .  Agr.,  p.  54. 


See  F.  H.  Chittenden, 


364       INSECT  PESTS  OF  FARM,  GARDEN  AND   ORCHARD 

occasionally  does  very  similar  injury  to  the  imported  cabbage 
worm.  The  caterpillar  is  about  three-fifths  of  an  inch  long, 
of  a  bluish-gray  color  above,  with  conspicuous  cross  stripes  of 
black,  as  shown  in  the  illustration.  The  parent  moth  is  a  pale 
ochre  yellow  color;  the  fore-wings  expand  about  an  inch,  and  are 
marked  with  brownish-black,  as  shown  in  the  illustration,  while 
the  hind-wings  are  nearly  transparent  except  at  the  outer  edge. 
Life  History. — The  caterpillars  are  to  be  found  on  cabbage  in 
late  May  and  early  June  at  Washington,  D.  C.  When  full  grown 
they  go  just  below  the  surface  of  the  earth  and  there  construct 


Fig.  264. — The  cross-striped  cabbage  worm  {Everyestis  rimosalis) :  a,  moth ; 
b,  egg-mass;  c,  sculpture  of  egg ;  d,  larva;  e,  cocoon — a,  d,  e,  twice  natuial 
size;  b,  much  enlarged;  c,  more  enlarged.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 


silken  cocoons  in  which  the  pupal  stage  is  passed  and  from  which 
the  moths  emerge  in  about  ten  days.  The  eggs  are  laid  in  masses 
of  a  bright  light-yellow  color,  from  twenty  to  forty  being  laid  in  a 
mass  on  the  under  surface  of  the  leaf,  and  hatch  in  about  a  week. 
The  caterpillars  become  full  grown  in  from  two  to  three  weeks, 
so  that  the  full  life  cycle  may  be  passed  in  thirty  days  in  mid- 
summer. It  seems  probable  that  at  Washington,  D.  C,  there 
are  three  generations  each  year,  and  that  the  winter  is  passed 
in  the  pupal  stage. 

Control. — The    same    means    of    control    advocated    for    the 
imported  cabbage  worm  will  prove  effcn-tive  for  this  species. 


INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS      365 

The  Imported  Cabbage  Webworm  * 

Sometime  in  the  early  90's  another  cabbage  pest  was  imported 
from  Europe,  where  it  is  common  in  the  Mediterranean  region,  and 
was  first  noted  as  injurious  in  South  Carolina.  Later  it  was  found 
in  Georgia  and  Alabama,  and  it  is  probable  that  it  has  now  become 
more  generally  distributed  through  the  Gulf  and  South  Atlantic 
States. 

The  imported  cabbage  webworm  is  about  one-half  an  inch  long, 


Fig.  265. — The  imported  cabbage  webworm  (Hellula  undalis  Fab.):  a,  moth; 
b,  larva  side  view;  c,  larva,  back  view;  d,  pupa — three  times  natural 
size.     (After  Chittenden,  U.  S.  Dept.  Agr.) 


of  a  grayish-yellow  color,  striped  with  five  brownish-purple  bands. 
Its  name  is  received  from  its  habit  of  spinning  a  silken  web, 
beneath  which  it  retreats  wdien  not  feeding,  and  to  which  masses 
of  excreta  and  frass  are  attached.  Cabbage  and  turnips  have 
been  most  injured,  but  various  other  cruciferse  are  attacked. 
The  parent  moth  has  a  wing  expanse  of  about  five-eighths  of  an 
inch  and  the  fore-wings  are  of  a  grayish  color,  mottled  with  brown, 
black  and  white  as  shown  in  the  figure. 

*  Hellula  undalis  Fab.  Family  Pyralidae.  See  F.  H.  Chittenden,  Bulletin 
19,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  51;  Bulletin  23,  Ibid.,  p.  54;  W.  M. 
Scott,  Bulletin  1,  Ga.  State  Board  Entomology",  p.  17. 


366         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Life  History. — The  life  liisiory  has  not  been  fohovvcd  for  the 
whole  season,  but  all  of  the  stages  have  been  ol)served.  Moths 
of  what  seemed  to  he  the  first  summer  generation  were  obtained 
in  late  Juh'.  The  eggs  are  aljout  onc-twenty-fifth  an  inch 
in  diameter,  oval,  and  of  a  grayish  color,  turning  pinkish  in  a 
day  or  two.  They  are  laid  singly,  usually  in  the  "  bud  "  of  the 
turnip  or  cal^bage.  With  a  temperature  of  80°  F.  they  hatched 
in  three  days.  The  caterpillars  become  full  grown  in  about 
eighteen  days,  and  then  spin  thin  cocoons  between  the  leaves 
in  which  they  transform  to  pupa?.  The  pupal  stage  requires 
but  about  a  week  in  midsummer,  so  that  the  moths  emerge  just 
about  a  month  after  the  eggs  were  laid.  The  most  serious  injury 
seems  to  occur  in  late  summer,  particularly  to  young  fall  cabbage 
and  turnips. 

Control. — Use  the  same  measures  as  advocated  for  the  imported 
cabbage  worm  and  the  cabbage  looper. 


The  Diamond-back  Moth  * 

The  larva  of  the  imported  diamond-back  moth  or  cabbage 
plutella  are  commonly  found  on  cabbage  wherever  it  is  grown, 
and  as  a  rule  do  but  little  injury,  though  occasionally  they 
become  trouljlesome. 

"  The  larva  when  full  grown  measures  three-tenths  inch  in 
length,  tapers  a  little  to  the  extremities,  and  is  of  a  pale  green 
color.  It  is  active  and  irritable,  in  this  respect  being  very 
different  from  any  of  the  larger  larvae  described."  The  wings 
of  the  parent  moth  "  are  kept  folded  against  the  sides  of  the  body, 
are  a  little  turned  up  at  the  tips,  and  are  provided  with  a  long 
fringe.  The  color  above  on  the  head,  thorax,  and  upper  part 
of  the  closed  wings  is  a  light  clay-yellow.  That  part  of  the 
wings  that  is  lowest  when  they  are  folded  is  bronzy  brown,  this 
color  terminating  abruptly  where  it  meets  the  clay-yellow  of 
the  back  by  a  well-defined  sinuous  margin.      The  length  from 

*  Plutella  maculipennis  Curtis.     Family  Tincidce. 


INJURIOUS  TO    CABBAGE  AND  CRUCIFEROUS  CROPS    307 

the  front  of  the  head  to  the  tip  of  the  folded  wings  is  about  one- 
fourth  inch."* 

"  The  eggs  are  whitish,  very  minute,  and  are  attached  to  the 
leaves,  though  sometimes  when  very  abundant  they  are,  it  is 
said,  placed  on  the  sides  of  crates  holding  cabbage."  The  full- 
grown  larvaj  pupate  in  small  cocoons  composed  of  a  delicate 
lace-work  of  silken  threads  through  which  the  whitish,  often 
brown-striped,  pupa  may  be  seen.  In  winter  the  cocoons  con- 
taining pupse  are  found  on  old  cabbage  stalks  in  the  field  or 
on  stored  cabbage.     Two  or  thr(>e  generations  a  year  occur  in  the 


Fig.  266. — The  cabbage  plutella  or  diamond-back  moth  (Phdella.  niaculi- 
pemiis  Curtis):  a,  larva;  b,  segment  of  same  greatly  enlarged;  d,  pupa; 
e,  pupa  in  cocoon;  /,  adult  moth;  g,  wings  of  dark  variety;  h,  moth 
with  wings  folded.     (After  Riley,  U.  S.  Dept.  Agr.) 

more  northern  States  and  four  or  five  generations  farther  south, 
while  in  the  extreme  South  it  may  be  found  active  practically 
throughout  the  year.  The  species  has  a  world-wide  distribu- 
tion. 

"  During  very  dry  weather  these  little  insects  become  exceed- 
ingly common,  and  riddle  the  cabbage  leaves  with  small  holes. 
Wet  weather,  on  the  other  hand,  has  long  been  known  to  be 
unfavorable  to  them,"  and  drenching  the  plants  with  water  has 
been  recommended  as  one  of  the  best  means  of  control.  The 
same  remedies  applied  for  the  other  cal^bage  worms  will  readily 
control  this  little  pest,  if  necessary. 

*  H.  Garman,  Bulletin  114,  Ky.  Agr.  Exp.  Sta.,  p.  29, 


368        INSECT  PESTS  OF   FARM,  GARDEN  AND  ORCHARD 


The  Harlequin  Cabbage-bug  * 

Southern    truckers    have    been    familiar   with   the    harlequin 
cabbage-bug,  "  calico-back,"    "  terrapin-bug,"    or   "  fire-bug,"  as 


Fig.  267. — The  harlequin  cabbage  bug  {Murgantia  histrionica  Hahn.):  a, 
eggs — enlarged;  h,  nymphs,  more  enlarged;  d,  adults  seen  from  above 
and  below — enlarged;  e,  head  and  beak  of  same;  /,  parasite  of  eggs — 
enlarged;  bugs  and  eggs  (a)  on  leaf,  natural  size.     (After  W.  G.  Johnson.) 

it  is  variously  called,    for  the   past   generation.      A  native   of 
Mexico  and  Central  America,   it  migrated  into  Texas  about  1864 

♦  Murgantia  histrionica  Hahn.  Family  Pentatomidoe.  See  F.  H.  Chitten, 
den,  Circular  103,  Bureau  Entomology,  U.  S.  Dept.  Agr.;  R.  I.  Smith, 
Journal  Economie  Entomology,  Vol,  II,  p.  108, 


INJURIOUS    TO    CABBAGE  AND   CRUCIFEROUS   CROPS     369 

and  then  spread  eastward  along  the  (!ulf  Coast,  and  northward 
until  it  reached  Maryland  'and  Virginia,  about  1880,  New 
Jersey  in  the  early  90's,  and  up  the  Mississippi  Valley  to  southern 
Ohio  and  Indiana  by  1890.  On  the  Pacific  Coast  it  is  found  in 
southern  California  and  Nevada.  Although  it  spread  to  Long 
Island,  N.  Y.,  southern  Pennsylvania,  and  northern  Ohio,  and 
Indiana,  its  advance  was  checked  by  the  cold  winters  of  the  late 


Fig.  268. — Field  of  cabbage  in  Delaware  ruined  by  the  harlequin  bug. 

90's  and  it  will  probably  never  become  very  injurious  north  of 
the  Potomac  and  Ohio  rivers. 

The  appearance  of  the  gayly  colored  bugs,  shining  black  or 
deep  blue,  marked  with  brilliant  red  or  orange,  as  shown  in 
Fig.  267,  is  so  distinctive  that  they  are  readily  recognized,  and 
given  them  the  name  of  harlequin-bug  or  calico-back.  They 
are  about  one-half  inch  long,  flattened,  and  the  general  shape 
and  markings  have  given  them  the  local  name  of  ''  terrapin 
bug."     The  bugs  suck  the  sap  from  the  leaves  of  cabbage  and  other 


370       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

erucifcrs,  the  plants  wilting  and  dying,  and  turning  black  as  if 
they  had  been  swept  by  fire;  hence  the  name  "  fire-bug."  A 
half-dozen  of  the  adult  bugs  will  destroy  a  small  plant  in  a  day 
or  two,  and  as  they  frequently  appear  in  enormous  numl)ers  and 
as  they  multiply  rapidly,  unless  they  are  fought  vigorously  they 
will  soon  destroy  a  large  patch  of  cabbage. 

Life  History. — The  adults  hibernate  over  winter  in  old  cabbage 
stumps  and  under  the  leaves  and  other  rubbish  left  on  the  field, 
and  emerge  early  the  next  spring.  In  South  Texas  they  may 
be  found  at  work  nearly  all  winter,  being  common  in  February 
and  March;  in  North  Carolina  they  appear  about  April  1st,  and  in 
Maryland  about  May  1st.  The  eggs  of  the  first  generation  are 
deposited  mostly  on  kale,  wild  mustard  or  other  wild  crucifera>, 
each  female  laying  about  100.  They  are  placed  in  a  double 
row  of  about  a  dozen  and  are  white,  marked  with  two  black  bands 
and  a  small  spot,  which  makes  them  look  like  small  white  barrels 
with  black  hoops.  The  eggs  of  the  spring  generation  hatch  in 
about  ten  days,  and  the  nymphs  feed  upon  the  cabbage  for  from 
six  to  nine  weeks  before  becoming  full  grown  in  North  Carolina 
and  the  District  of  Columbia,  while  in  the  Gulf  States  the  eggs 
hatch  in  four  to  eight  days  and  the  nymphs  become  full  grown 
in  three  or  four  weeks,  the  development  of  these  stages  being 
determined  by  the  temperature.  The  nymphs  are  much  like 
the  adults  in  coloration,  though  differently  mai-ked  and  lacking 
wings.  They  molt  five  times,  some  of  the  diffei-ent  stages  being 
shown  in  the  figure.  From  North  Carolina  northward  there 
seem  to  be  but  three  generations  of  the  insect.  The  summer 
generation  develops  more  rapidly,  the  eggs  hatching  in  four  or 
five  days,  Ijut  the  fall  generation  requires  about  the  same  time  as 
in  spring.  In  midsummer  the  whole  life  cycle  may  be  passed  in 
about  two  weeks  in  the  Gulf  States,  according  to  various  author- 
ities, so  that  there  may  be  a  half  dozen  generations,  though  the 
exact  life  history  does  not  seem  to  have  been  observed  there. 

Control. — This  is  an  exceedingly  difficult  pest  to  combat  after 
it  has  become  numerous  in  the  cabbage  patch,  so  that  every  effort 
should  be  made  to  prevent  its  appearance.     As  it  hibernates  under 


INJURIOUS  TO    CABBAGE  AND   CRUCIFEROUS   CROPS      371 

old  stalks  and  leaves  it  is  obvious  that  they  slujuld  he  elcaiied  up 
and  the  field  plowed  as  soon  as  the  crop  is  harvested.  By  leaving 
a  few  piles  of  stalks,  leaves  and  rubbish,  the  ])ugs  might  be  concen- 
trated and  then  destroyed. 

The  most  successful  method  of  control  yet  devised  is  the  use 
of  a  trap-crop,  to  which  the  bugs  are  lured  as  they  emerge  from 
hibernation  and  on  which  they  may  be  destroyed  before  they 
attack  the  caljbage.  Kale  planted  in  the  fall  or  mustard  planted 
early  in  the  spring  serves  well  for  a  catch  crop,  and  should  be 
planted  in  rows  through  the  intended  cabbage-field.  The  bugs 
seem  to  prefer  the  kale  to  the  young  cabbage,  and  while  concen- 
trated upon  it  they  should  be  killed  by  spraying  them  with  pure 
kerosene.  The  trap-crop  may  well  be  planted  at  different  dates, 
so  that  after  one  row  has  been  destroyed  by  spraying,  another  will 
invite  the  remaining  luigs.  The  nymphs  may  be  destroyed  by 
spraying  them  with  15  per  cent  kerosene  emulsion  or  whale-oil  soap, 
one-half  pound  per  gallon.  Whale-oil  soap  used  at  the  rate  of  1^  to  2 
pounds  to  the  gallon  will  kill  most  of  the  adult  bugs  hit  by  it 
without  injury  to  the  cabbage,  but  dependence  should  not  be 
placed  upon  control  by  spraying,  as  its  practicability  on  a  large 
scale  is  yet  to  be  demonstrated. 

The  Cabbage-aphis  * 

Wherever  cabbage  is  grown  the  common  "  cal)bage-louse  " 
occasionally  becomes  abundant  enough  to  do  serious  damage, 
often  destroying  young  plants,  which  become  covered  with  the 
disgusting  masses  of  grayish  aphides.  They  are  found  commonly 
in  almost  every  cabbage -patch,  but  usually  their  natural  enemies 
are  so  effective  as  to  prevent  their  increase;  otherwise  they  would 
l)e  one  of  the  most  serious  pests  of  cruciferous  crops.  They  may 
be  found  on  all  of  the  cultivated  and  wild  cruciferie,  l)ut  cabbages 

*  Aphis  brassicce  Linn.  Family  Aphididae.  See  C.  V.  Riley,  Report  of 
U.  S.  Commissioner  of  Agriculture,  18S4,  p.  317.  C.  M.  Weed,  "  Insect 
Life,"  Vol.  Ill,  p.  289.  G.  W.  Herrick,  Journal  of  Economic  Ent.,  Vol.  IV. 
p.  219?  F.  H.  Chittenden  and  C.  H.  Popenoe,  Bulletin  2,  Va.  Truck  Exp. 
Sta.,  p.  22. 


372         IN8ECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

unci  turnips  urc  injured  worst,  sciious  (huna<i(>  often  being  done  to 
turnips  in  the  South. 

"  The  wingless  viviparous  female  has  a  rather  long  oval  body, 
covered  with  a  whitish  mealy  coat.  When  this  coat  has  ])een 
i-emoved  .  .  .  the  body  is  seen  to  be  a  grayish-green  color,  with 
eight  l)lack  spots  dow^n  either  side  of  the  back,  increasing  in  size 
toward  the  posterior  end.  The  antenme  are  green  with  black  tips 
and  are  shorter  than  the  body,  and  the  eyes,  legs  and  tail  are 
black.  The  young  when  first  hatched  are  oval,  shining,  bright 
yellow  in  color,  and  lack  the  mealy  coat.  The  winged  viviparous 
female  is  yellowish-green,  with  the  eyes,  neck  and  thoracic  lobes 
black,  and  the  antenna?  and  nectaries  dark  V)i'own.     The  legs  are 


Fig.  269. — The  cabbage-aphis   {{phis  brassier  Linn.):    a,  winged  form;  6 
wingless  viviparous  female — Greatly  enlarged.      (After  Curtis.) 

dusky  brovv-n  and  hairy;  the  tail  is  dark  green  or  l)rown  and  also 
hairy;  the  wings  are  I'ather  short,  with  stout  coarse  A-eins  and  dai'k 
stigma."     (Riley). 

Life  History. — Though  the  cal)l)age-aphis  is  an  oUl  ]*]ui'opean 
species  and  was  observed  in  this  country  as  early  as  the  latter  part 
of  the  eighteenth  century,  its  life  history  has  only  recently  Ijcen 
carefully  worked  out  by  Professor  G.  W.  Herrick  and  Mr.  J.W.  Hun- 
gate  of  Cornell  University  (I.e.),  from  whose  account  the  following 
is  taken: 

The  oviparous  females  appear  in  the  fall  and  are  fertilized  by 
the  males,  and  deposit  their  eggs  in  large  numbers  on  the  leaves 
of  the  cabbage,  during  Octoljcr  and  the  first  days  of  November, 
in  central  New  York.     The  eggs  are  laid  on  rape,  turnip,  brussels 


INJURIOITS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS      373 

sprouts  and  kolil-rubi,  l)ut  are  most  abundant  on  cubljage,  particu- 
larly in  the  crevices  and  depressions  of  the  under  surfaces  of  the 
leaves.  On  leaves  taken  at  random  from  a  l:)adly  infested  patch, 
from  177  to  293  eggs  were  found  on  a  leaf.  Two  to  three  eggs  arc 
laid  b}'  each  oviparous  female.  When  first  laid  the  eggs  are  a 
yellowish-green,  but  soon  turn  a  shining  l)lack.  From  eggs  taken 
at  random  and  left  under  normal  outdoor  conditions,  76  per  cent 
hatched  the  next  spring,  while  all  eggs  hatched  which  were  laid  by 
females  known  to  have  been  fertilized.  Eggs  hatched  about 
Api'il  1,  1!)1(),  in  c(nitral  Xew  Yoi'k,  tiie  season  being  an  eai'ly  one. 
From  the  stem  mothers  which  hatched  from  these  eggs,  twenty- 
one  generations  of  wingless  females  were  reared  up  to  December  3, 
1910,  the  average  length  of  a  generation  being  about  twelve  days. 
During  the  summer  generations  of  winged  females  are  produced, 
especially  on  crowded  plants,  and  these  serve  to  spread  the  pest  to 
unaffected  plants.  The  wingless  females  become  full  grown  in 
about  thirteen  days  during  the  summer  and  live  for  aljout  forty-six 
days,  during  which  time  tliey  will  give  birth  to  an  average  of  forty- 
one  young,  producing  as  high  as  six  young  in  a  day.  The  winged 
forms  are  much  shorter  lived,  living  only  about  ten  days  and  giving 
birth  to  but  from  seven  to  thirteen  young. 

There  is  no  question  that  in  the  Southern  States  the  viviparous 
females  may  continue  to  reproduce  all  winter,  and  it  is  quite  prob- 
able that  some  of  them  survive^  in  pits  and  cellars  in  the  North, 
where  eggs  also  probably  occur.  Thus  Sirrine*  states  that  it  "  is 
certain  that  this  aphid  can  survive  the  winter  on  cabbage  stored 
in  cellars  or  pits,  also  that  cabl^age  stored  in  pits  for  seed  purposes 
furnishes  the  supply  of  aphides  for  infesting  the  seed  stalks  in  early 
spring."  This  being  the  case  it  should  be  an  easy  matter  to 
destroy  the  aphides  by  fumigation  before  removing  them  from 
the  pits. 

Control. — From  the  ha]:)its  outlined  it  is  evident  that,  as  for 

other  cabbage  pests,  the  refuse  of  the  crop  should  be  cleared  up  and 

destroyed  in  the  fall.     Any  of  the  standard  contact  insecticides, 

such  as  kerosene  emulsion,  1  part  stock  solution  to  15  parts  of 

*  F,  A.  Sirrine,  Bulletin  S3,  N.  Y.  Agr.  Exp.  Sta.,  p.  67.3 


374         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

water,  whale  oil-soap,  1  pound  to  6  gallons,  or  black  leaf-tobacco 
extract,  1  part  to  64  of  water,  will  destroy  the  aphides,  but  the 
spraying  must  be  thorough,  as  the  waxy  coating  serves  to  pro- 
tect them.  According  to  Professor  Franklin  Sherman,  any  good 
laundry  soap  used  at  the  rate  of  1  pound  dissolved  in  3  gallons  of 
water,  will  destroy  the  aphides.  Where  water  under  pressure  is 
available  in  a  small  garden,  the  aphides  may  be  held  in  check  by 


Fig.  270. — The  spinach-aphis  {Mijzus  persiav  Sulz.):  which  often  becomes 
a  cabbage  pest:  a,  winged  adult;  h,  young  nymph;  c,  older  nymph;  d, 
last  stage  of  nymph — all  greatly  enlarged.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 

washing  them  from  the  plants  with  a  strong  stream  from  a  garden 
hose.  Plants  infested  in  the  seed-bed  may  be  freed  from  the 
aphis  by  dipping  in  whale-oil  soap  solution,  1  part  to  S  of  water. 

Fortunately  for  the  grower,  the  cabbage-aphis  is  usually  held 
in  check  by  numerous  parasitic  enemies,  principally  little  wasp- 
like flies  of  the  family  Braconidse,  and  by  several  species  of  lady- 
bird-beetles and  syrphus-fly  larvse,  which  will  often  destroy  a 
colony  within  a  few  days. 


INJURIOUS  TO  CABBAGE  AND  CRUCIFEROUS  CROPS       375 

The  Spinach-aphis  or  Green  Peach-aphis  '' 

Another  species  of  apliis  oft  cm  l^ecomes  dcstructivo  to  cabbage, 
spinach,  celery  and  lettuce,  as  well  as  various  greenliouse  crops. 
In  the  fall  it  migrates  to  peach,  and  is  also  known  as  the  green 
p(>ach-aphis,  as  which  it  is  discussed  on  page  658. 

Flea-beetles  f 

A  considerable  number  of  small  flea-beetles  attack  cabbage  and 
other  cruciferous  crops,  and  although  as  a  rule  only  troublesome, 
they  appear  periodicalh'  in  enormous  numljers  and  do  serious 
injur}'.  The}'  are  mostly  small  species  (there  being  seven  species 
of  the  genus  Phyllotreta  alone)  not  over  an  eighth  of  an  inch  long. 
One  of  the  most  common  throughout  the  country  is  the  striped 
turnip  flea-beetle. J  It  is  polished  black  with  each  wing-cover 
marked  with  a  broad,  wavy  band  of  pale  yellow.  The  microscopic 
white  eggs  are  laid  in  a  little  excavation  of  the  root  near  the  crown 
of  the  plant.  The  larvse  mine  into  the  roots  and  have  been 
reported  to  do  considerable  injury  to  them,  but  it  seems  probable 
that  most  of  them  live  upon  the  roots  of  cruciferous  weeds.  The 
full  grown  larva  (Fig.  270,  a)  is  about  three-eighths  inch  long, 
quite  slender  and  tapering,  yellowish  white,  with  brown  head  and 
anal  plate,  antl  with  marks  on  the  thorax  and  transverse  rows  of 
minute  hair-bearing  tul)ercles  as  shown  in  the  figure.  The  West- 
ern cabbage  flea-beetle  §  is  the  more  common  from  the  Dakotas 
southward  to  Mexico  and  westward  to  southern  California.  It  is  a 
uniform  deep  olive-green,  with  the  surface  irregularly  punctate, 
and  ^/loo  inch  long.  Another  species  almost  indistinguishable  from 
the  first  species  above,  is  the  wavy-striped  flea-l)eetle,^  whose  larva; 
mine  in  the  leaves  of  wild  pepper  grass  {Lepidium  virginicum), 

*  Myzus  persicoe  Sulz.     See  footnote  on  page  658. 

t  Family  Chrysomelidce.     Refer  to  pages  296,  335,  for  other  flea-beetles. 
See.  C.  V.  Riley.  Report  U.  S.  Commissioner  Agr.,  for  1S<S4,  pp.  301-308. 
X  Phyllotreta  vittata  Fab. 
§  Phyllotreta  pusilla  Horn. 
^  Phyllotreta  sinuata  Steph.    {zimmermani  Crotch.) 


37G       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  is  most  abuiulaut  in  the  Middle;  and  Southern  States.     The 
life  history  has  been  fully  described  by  Dr.  Riley  (I.e.). 

Control. — Where  the  plants  are  sprayed  for  the  ea])bage  worms 
with  Paris  green  or  arsenate  of  lead,  there  will  proljably  be  little 
trouble  with  flea-beetles.  Otherwise,  spray  with  arsenate  of  lead, 
3  to  5  pounds  per  barrel,  or  Paris  green  one-third  to  one-half 
pound,  adding  the  resin  soap  (see  page  46)  or  "  sticker,"  so  as  to 
give  the  foliage  a  good  thick  coating,  for  the  spray  probably  acts 
fully  as  much  as  a  repellant  as  a  remedy.  Where  injury  is  antici- 
pated it  will  be  well  to  dip  the  plants  in  arsenate  of  lead  1  pound 


Fig.  271. — The  i<triped  turnip  flea- 
beetle  (PItyllotrela  vitlata  Fab.): 
a,  larva;  b,  adult — greatly  en- 
larged. (After  Riley,  U.  S.  D. 
Agr.) 


Fig.  272. — The  we.~tern  cabbage  flea- 
beetle — much  enlarged.  (After  Riley, 
U.  S.  Dept.  Agr.) 


to  10  gallons  of  water  when  planting  them.  By  thoroughly  dust- 
ing the  plants  with  lime,  land  plaster,  strong  tobacco  dust,  dilute 
pyrethrum,  or  any  of  the  dusts  commonly  usetl  for  such  insects, 
applying  the  dust  in  the  early  morning  while  the  dew  is  on  the 
plants,  they  may  be  protected  from  attack  as  long  as  they  are 
kept  thoroughly  covered.  It  is  evident  that  the  weeds  upon 
which  these  pests  develop  in  th(>  larval  stage  should  be  destroyed. 
Where  plants  are  attacked  in  the  seed-bed,  screening  as  advised 
for  the  root-maggot  will  prevent  injury.  Cloth  with  from  20  to  30 
threads  to  the  inch  has  proven  most  satisfactory  for  the  screens, 
which  should  Iw  applied  early  and  be  made  perfectly  tight. 


INJURIOUS   TO  CABBAGE   AND  CRUCIFEROUS  CROPS     377 

The  Cabbage  Curculio  * 

A  small  weevil  has  proven  injurious  to  early  cabbage,  particu- 
larly in  seed-beds,  in  Wisconsin,  Ohio,  and  Missouri  and  elsewhere. 
The  cabbage  curculio  is  a  native  of  middle  and  northern  Europe, 
where  it  is  not  known  as  doing  much  injury,  and  was  first  noticed 
in  this  country  in  Massachusetts  in  1873.  Since  then  it  has  spread 
over  the  Northern  States  and  occurs  in  California. 

The  adult  weevil  is  of  a  broad,  oval  shape,  about  one-eighth 
inch  long,  and  is  covered  with  gra^'ish  scales,  l)ut  is  l)lackish  when 


Fig.  273. — The  cabbage  curculio  {Ceu'orhmchus  rape  Gyll.):  a,  beetle; 
b,  same  in  profile;  c,  larva;  d,  head  of  same;  e,  pupa  in  cocoon;  a,  b,  c,  e, 
eight  times  natural  size;  d,  more  enlarged.  (After  Chittenden,  U.  S.  D. 
Agr.) 

these  are  rubbed  off  in  old  specimens.  The  weevils  appear  about 
the  middle  of  April  at  Washington,  D.  C,  and  lay  their  eggs  in  the 
leaf  stalks  late  in  April.  The  grayish,  oval  egg  is  about  one  thirty- 
fifth  inch  long,  and  is  inserted  in  a  cavity  eaten  out  by  the  female, 
which  causes  a  very  noticeable  scar.  The  eggs  hatch  in  about  a 
week.  The  white,  footless  larvae  are  about  one-fourth  inch  long 
antl  bore  into  the  leaf-stems  and  stalks.  "  Larvae  are  found  most 
numerous  in  the  upper  portion  of  stems,  penetrating  frequently  as 

*  Ccutorlnjncuft  rap(B  Gyll.  Family  Curculionida.  See  F.  H.  Chittenden, 
Bulletin  2:5,  n.  s.,  Bureau  of  Ent.,  U.  S.  Dept.  Agr.,  p.  ;i9,  and  F.  M,  Webster^ 
Bulletin  77,  Ohio  Agr.  Exp.  Sta.,  p.  50. 


378        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

high  as  the  diameter  of  the  stem  will  admit  them.  They  also  bore 
into  the  branches,  and  occasionally  a  short  distance  into  the  leaf- 
stalks. ...  In  many  cases  the  leaf-stalks  are  killed  or  are  so 
injured  that  they  part  from  the  stems  when  the  latter  are  pulled 
up;  and  again,  the  stems,  being  so  closely  tunneled,  often  part  above 
the  middle,  even  dropping  over,  though  not  handled."  The  larvae 
complete  their  growth  in  about  three  weeks,  cut  their  way  out  of 
the  stalks  and  enter  the  earth,  where  they  form  small  earthen 
cocoons  just  beneath  the  surface.  In  these  they  transform  to 
pupae,  from  which  the  beetles  emerge  in  about  a  week.  The  beetles 
are  common  in  the  middle  of  June  at  Washington,  Ijut  disappear 
late  in  the  month. 

A  fortunate  fact  is  that  "  cabbage  appears  to  be  one  of  the  last 
plants  attacked  in  the  field  when  any  other  palatable  crucifer  is 
obtainable.  The  beetles  not  only  greatly  preferred  hedge  mus- 
tard {Sisymbrium  officinale),  and  wild  pepper  grass,  but  appeared 
to  attack  also,  by  preference,  turnip,  horseradish  and  cauliflower."* 

Control.— T\\h  fact  of  the  preference  of  the  beetles  for  the  wild 
food-plants  might  be  utilized  by  using  them  as  a  trap-crop,  planting 
them,  if  necessary,  as  advised  for  the  harlequin  cabbage-bug 
(page  371),  and  then  removing  and  destroying  them  as  soon  as  the 
beetles  had  oviposited,  which  would  probably  be  about  the  middle 
of  May  in  the  latitude  of  Washington,  D.  C.  Although  no  prac- 
tical experiments  in  its  use  seem  to  have  been  tried,  a  thorough 
application  of  arsenate  of  lead  at  from  3  to  5  pounds  to  50  gallons 
would  undoul)tedly  destroy  many  of  the  beetles  when  they  are 
feeding  on  the  foliage  in  early  spring  and  after  they  emerge  in  June. 

*  Quotations  from  Chittenden,  I.e. 


CHAPTER  XIX 

INSECTS    INJURIOITS    TO   MELONS,  CUCUMBERS,   SQUASH,   ETC.* 

The  Striped  Cucumber-beetle  t 

Just  as  the  httle  cucumber  and  melon  plants  appear  above  the 
soil  they  are  attacked  by  hordes  of  hungry  black-and-yellow-striped 
beetles,  Avhich  feed  ravenously  upon  the  succulent  seed-leaves 


Fig.  274. — The  .striped  cucumber  beetle  {Diabrolica  vittata  Fab.):  a,  beetle; 
b,  larva;  c,  pupa;  d,  egg;  e,  sculpture  of  egg — a,  b,  c,  much  enlarged; 
d,  more  enlarged;  e,  highly  magnified.  (After  Chittenden,  U.  S.  D, 
Agr.) 

often  killing  them  entirely  so  that  reseeding  is  necessary.  This 
little  striped  beetle,  often  known  as  the  "  striped-bug  "  or  "  melon- 
bug,"  is  well  known  to  all  growers  of  cucurbs  east  of  the  Rocky 
Mountains,  and  also  occurs  in  Washington. 

*  See  A.  L.  Quaintance,  Bulletin  45,  Geo.  Agr.  Exp.  Sta.;  J.  B.  Smith, 
Bulletin  94,  N.  J.  Agr.  Exp.  Sta..;  R.  I.  Smith,  Bulletins  205  and  214,  No. 
Car.  Agr.  Exp.  Sta. 

t  Diabrotica  vittata  Fab.  Family  Chrysomelidoe.  See  F.  H.  Chittenden, 
Circular  31,  Bureau  Ent.,  U.  S.  Dept.  Agr.;  T.  J.  Headlee,  20th  Report  N.  H. 
Agr.  Exp.  Sta,,  p.  499, 

379 


380 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  beetle  is  about  two-fifths  inch  long  and  half  as  wide,  of  a 
Ijright  yellow  color  with  a  black  head  and  three  black  stripes  on  the 
wing-covers. 

Life  History. — The  beetles  hibernate  over  winter  in  the  ground 
where  they  have  been  feeding  the  previous  fall,  or  along  the  edge  of 
woodlands,  or  wherever  suitable  shelter  is  obtained,  and  emerge 
in  the  spring  two  or  three  weeks  before  cucurbs  are  planted.     At 

this  season  they  seem  to  feed  on  al- 
most anything,  as  they  have  been 
ol)served  feeding  on  a  long  list  of 
food-plants,  frecpie  ting  flowers  whose 
petals  are  eaten.  As  soon  as  squash, 
melons,  or  cucumbers  break  through 
the  soil,  they  gather  upon  them  and 
refuse  all  other  food.  If  the  foliage  is 
covered  with  any  offensive  substance 
they  will  seek  out  spots  which  have 
not  been  reached  and  feed  upon  them, 
which  fact  is  of  importance  in  con- 
sidering remedies.  After  feeding  upon 
cucurbs  for  a  few  days  the  beetles  pair 
and  the  females  commence  to  deposit 
Fig.  275.— Larva  of  striped  (^gg^-  The  eggs  are  deposited  singly 
cucumber  beetle  at  work  .^j^j  ^re  merely  dropped  in  crevices  of 
in  cucumber  stem.    (Photo      ,  .,  .    '  .  ,    ^, 

by  Headlee.)  the   soil    or  m  the  openmg  around  the 

stem  of  the  plant.  The  egg  is  oval, 
about  one-fortieth  inch  long,  l^right  yellow,  and  sculptured  with 
microscopic  hexagonal  pits.  A  female  lays  about  one  hundred 
eggs  during  a  period  of  a  month,  and  they  hatch  in  about  eight 
days  at  a  mean  temperature  of  74°  F.  The  larva  is  a  slender, 
white,  worm-like  grul),  al)out  three-tenths  inch  long,  with  dark- 
brown  head  and  anal-plate,  and  lighter  brown  thorax.  The  larva; 
bore  into  the  roots,  often  tunneling  into  the  base  of  the  stem,  and 
sometimes  mine  into  melons  lying  on  damp  soil.  Rarely  does 
injury  ])y  the  larva;  liecome  noticeable,  though  we  have  observed 
whole  patches  of  cucumber  and  melon  vines  killed  by  them,  whicli 


INJURIOUS   TO   MELONS,  CUCUMBERS,   SQUASH,  ETC.      381 

seems  reiiuirknblc,  cousiderinf;'  the  immense  miml)(>rs  of  the  l^ectles 
whieh  must  give  rise  to  many  times  more  hirvte.  Tlie  hirva 
IxH'omes  full  grown  in  ul)out  a  month  and  then  forms  a  delicate 
earthen  cell  just  below  the  surface  of  the  soil  and  in  it  transforms 
to  the  whitish  pupa,  from  which  the  beetle  emerges  in  from  one  to 
two  weeks,  according  to  the  temperature.  In  southern  New 
Hampshire  the  beetles  emerge  from  the  last  of  August  to  the  first  of 
October,  the  complete  life  cycle  requiring  from  seven  co  nine  weeks, 
there  being  l^iit  one  generation  a  year,  and  this  seems  to  be  true 
in  New  York.     In   Kentucky  the   complete   cycle  requires  but 


Fig.  276. — Wire  screen  cover  for  j'oung  cucurbs.     (After  Headlee.) 

thirty-nine  days,  and  in  the  District  of  Columbia  newly  emerged 
beetles  are  found  by  mid-July,  so  that  there  are  imdoubtedly  two 
generations  in  that  latitude,  as  the  ])eetles  have  been  found  pairing 
and  with  well-developed  eggs  in  Delaware,  August  1st.  In  the 
latter  part  of  the  season  the  beetles  feed  on  the  blossoms  and 
pollen,  particularly  of  squash,  rarely  touching  the  foliage.  With 
the  first  frosty  nights  they  seek  shelter  under  the  fallen  leaves  and 
enter  hibernation  with  the  first  killing  frosts. 

Control. — For  a  few  plants  or  where  the  beetles  are  unusually 
abundant,  coverings  of  netting  have  always  been  used  to  protect 
the  plants.  A  barrel  hoop  cut  in  two,  crossed,  and  the  ends 
fastened  to  another  hoop,  and  the  whole  then  covered  with  netting. 


382     INSECT  PESTS  OF  FARM,   GARDEN   AND  ORCHARD 

makes  an  admirable  cover,  often  sold  by  dealers.  Two  stout  wires 
bent  into  arches  and  crossed,  may  also  be  covered  with  netting, 
the  lower  edge  of  which  is  held  by  earth  packed  over  the  edges- 
Or  cone-shaped  covers  may  be  fashioned  out  of  wire  screening  and 
kept  from  year  to  year.     (See  Headlee,  I.e.) 

Many  growers  obviate  loss  of  plants  and  the  necessity  of 
replanting  by  sowing  the  seed  in  rows  rather  thickly  and  then  thin- 
ning out  to  the  desired  distance  after  the  worst  injury  by  the  beetle 
is  passed.  Others  make  several  plantings  in  each  hill  at  intervals 
of  a  week,  l)ut  the  former  plan  will  ensure  earlier  growth. 

The  growing  of  rows  of  early  l:)cans  to  act  as  a  trap-crop  has 
been  suggested,  as  the  beetles  will  gather  on  them,  it  is  said,  and 
having  an  abundance  of  food  will  not  injure  the  cucurbits.  Squash 
may  be  effectively  used  in  this  way  as  the  beetles  are  peculiarly 
fond  of  the  quick-growing  squash  seedlings.  A  week  or  ten  days 
before  the  regular  crop,  plant  rows  of  squash  seed  around  and 
through  the  prospective  field,  and  plant  more  rows  when  the  regu- 
lar crop  is  planted.  If  the  main  crop  be  kept  well  dusted  or 
sprayed  as  advised  below,  the  beetles  will  concentrate  on  the  trap- 
squash  and  might  be  destroyed  upon  it  by  spraying  with  pure 
kerosene. 

Liberal  fertilization  with  quick-acting  fertilizers  will  aid  the 
young  plants  to  make  a  quick  growth  and  thus  outgrow  the  injury. 

Growers  have  long  known  that  if  the  plants  are  kept  thoroughly 
covered  with  some  sort  of  dust  that  the  beetles  will  not  molest 
them,  and  various  sprays  have  been  used  in  the  same  way  To  be 
effective  the  plants  must  be  dusted  in  early  morning  while  the 
dew  is  on  and  all  parts  of  the  plant,  above  and  below,  must  be 
thoroughly  covered.  This  must  be  repeated  as  often  as  the  dust 
is  washed  or  blown  off,  or  the  plant  outgrows  it.  Air-slaked  lime 
mixed  with  sulfur,  tobacco  dust,  and  bug-death  have  been  the  most 
effective,  though  similar  powders  will  be  found  beneficial.  Bor- 
deaux mixture  has  been  recommended  for  this  purpose,  but  seems 
to  have  a  stunting  effect  on  the  young  plants.  The  most  valuable 
repellant  seems  to  be  a  spray  of  arsenate  of  lead  3  to  5  pounds  per 
barrel.     This  not  only  repels  the  beetles  better  than  any  other 


INJURIOUS  TO   MELONS,  CUCUMBERS,  SQUASH,  ETC.     383 

substance  tested  by  Dr.  Headloe,  but  undoul)tedly  kills  many  of 
those  which  arc  forced  to  feed  upon  it.  Professor  Gillette  re})orts 
that  dry  pyrethrum  dusted  on  the  plants  while  the  dew  is  on  will  kill 
many  of  the  insects.  Sirrine  found  that  in  New  York  the  beetles 
could  be  poisoned  successfully  with  Paris  green,  but  only  while 
feeding  in  the  spring  before  they  commenced  to  pair,  and  in  the 
fall,  as  they  refused  protected  foliage  after  pairing  commenced. 
Various  repellants,  such  as  kerosene,  turpentine,  naphthalene  or 
moth  balls,  and  other  similar  odoriferous  substances,  have  been 
strongly  recommended,  but  careful  tests  have  not  demonstrated 
their  efficiency. 

It  is  evident  that  the  cleannig  up  of  vmes  as  soon  as  the  crop 
can  be  gathered  and  the  destruction  of  all  refuse  will  deprive  the 
beetles  of  food  in  the  fall  and  force  them  to  seek  other  hibernating 
places,  thus  increasing  the  mortality. 

The  Melon-aphis  * 

Just  as  the  vines  commence  to  run,  a  plant  will  be  found  here 
and  there  with  the  foliage  curled  up  and  wilting  and  within  will  be 
found  masses  of  the  greenish  "  melon  lice,"  w^hich  have  caused  the 
injury  by  their  many  beaks  sucking  out  the  sap  of  the  plant.  If 
allowed  to  multiply  unchecked  and  their  natural  enemies  do  not 
prevent  their  increase,  they  will  sometimes  become  so  abundant 
as  -.0  completely  ruin  a  whole  crop  just  as  the  melons  are  com- 
mencing to  ripen.  It  is  one  of  the  worst  pests  of  cucurbs  and  one 
which  requires  constant  vigilance  on  the  part  of  the  grower. 

The  aphides  are  to  be  found  on  various  weeds  in  early  spring 
and  appear  on  cucurbs  soon  after  they  start  growth.  Both  winged 
and  wingless  females  occur  throughout  the  year.  The  wingless 
form  is  about  one-fifteenth  inch  long  and  varies  from  light  yellow 
or  tan  colored  to  deep  olive-green  or  deep  green  which  appears 
almost  blackish,  the  abdomen  being  always  more  or  less  mottled. 
The  rather  long,  tapering,  honey-tubes  are  jet  black,  and  the  legs 
and  antennae  pale  whitish-yellow.     The  young  nymphs  always 

*  Aphis  gossypii  Glover.  Family  Aphididoe.  See  F.  H.  Chittenden, 
Circular  80,  Bureau  ofEnt.,  U.  S.  Dept.  Agr. 


384  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

show  a  distinct  yellowish-brown  or  pale  salmon-colored  area  just 
in  front  of  the  honey-tubes  and  a  dark  transverse  l^and  between 
them.  The  nymphs  of  the  last  stage,  in  which  the  wing  pads  are 
visible,  are  marked  on  the  back  with  little  flecks  of  silvery  white, 
waxy  bloom.  The  winged  female  is  about  the  same  length  and  the 
wings  expand  one-fifth  to  one-quarter  inch.     The  color  varies  as 


Fig.  277. — The  melon  aphis  (Aphis  gossypii  Glov.):  a,  winged  female;  aa, 
enlarged  antenna  of  same;  ah,  dark  fen>ale,  side  view,  sucking  juice 
from  leaf;  fc,  young  nymph;  c,  last  stage  of  nymph  of  winged  form; 
d,  wingless  female — greatly  enlarged.     (After  Chittenden,  U.  S.  D.  Agr.) 


in  the  wingless  form,  but  there  are  black  spots  along  the  sides 
of  the  abdomen,  and  the  head  and  thorax  are  dark  as  shown  in 
Fig.  277. 

The  melon-aphis  is  found  throughout  the  country  southward 
through  Central  America,  and  though  it  often  does  serious  damage 
in  the  North  it  is  worse  in  the  South.     It  has  a  long  list  of  food 
plants,  among  the  crops  injured  by  it  homg  all  the  ciicurbs,  cotton, 


INJURIOUS  TO  MELONS,    CUCUMBERS,  SQUASH,   ETC.      385 

okra,  oniiigv,  and  its  oeca.sional  fo{Kl-])lant.s  include  niaii\-  others, 
as  it  is  found  on  a  long  list  of  weeds,  most  abundantly  on  shep- 
herd's purse  and  pepper-grass,  upon  which  it  multiplies  in  early 
spring  and  probably  passes  the  winter. 

Life  History. — The  life  history  is  much  the  same  as  that  of  most 
of  our  common  aphides,  though  of  some  phases  we  are  still  in 
ignorance  in  spite  of  the  most  careful  stud}'.  The  females  give 
birth  to  from  four  to  ten  aphides  a  day,  depending  upon  the  tem- 
perature and  food  supply,  and  these  become  full  grown  in  from  six 
to  eight  days.  As  the  affected  leaf  becomes  non-succulent  the 
aphides  migrate  to  another  leaf  and  often  cluster  on  the  terminal, 
which  is  checked  and  stunted.  As  they  become  more  nuitierous, 
winged  forms  migrate  to  other  plants  and  within  two  weeks  a 
colony  of  fifty  or  more  will  form  the  progeny  of  every  one  born 
by  the  immigrating  female.  Reproduction  seems  to  go  on  this 
way  throughout  the  year,  being  stopped  only  l^y  the  cold  of  win- 
ter, as  far  as  has  been  observed.  No  true  sexual  forms  or  eggs,  as 
are  known  to  occur  with  other  nearly  related  species,  have  been 
observed,  and  the  viviparous  forms  have  been  found  throughout 
the  winter  in  Colorado  and  Texas. 

Enemies. — Fortunately  the  melon-aphis  is  subject  to  the  unre- 
mitting attack  of  many  insect  enemies,  the  list  including  some 
thirty-five  species.  Among  the  more  important  are  the  common 
la,dy]iird-l)eetles  and  their  larva\  of  which  the  convergent  ladv- 
bird,*  tlic  nine-spotted  ladybird, f  and  the  spotted  ladybird, | 
shown  in  Figs.  1-5,  are  among  the  most  effective,  and  the  maggots 
of  various  common  sja'phus-flies,  and  the  aphis-lions.  §  Even 
more  beneficial  are  the  little  parasitic  flies  whose  larvae  live  within 
the  maggots  and  destroy  myriads  of  them  wath  incredible  swift- 
ness. The  most  common  of  these  t  are  the  same  as  the  most 
common  parasite  of  the  green  bug  (Fig.  113),  and  they  often  destroy 
the  aphides  over  a  wdiole  field  in  a  few  days.     They  are  most  effect- 

*  Hippodamia  convergens  Guer. 

t  Coccinella  9-notata  Herbst. 

X  Megilla  maculata  DeG.     Family  Cocci nellidae. 

§  Family  Chrysopidoe. 

•[[  Lysiphlebus  testaceipes  Cress.     Family  Braconidoe. 


386        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fifl.  278. — Melon  aphides  whidi  have  been  killed  by  parasites  on  cotton  leaf. 


INJURIOUS  T(^    MELONS,   CUCUMBERS,   SQUASH,  ETC.     387 

ive  in  bright,  warm  weather,  when  tliey  repi'ochice  most  rapidly, 
but  in  cool,  moist  weather  they  reproduce  but  slowly,  and  if  such 
a  summer  follows  similar  weather  conditions  during  the  spring,  the 
aphides  multiply  rapidly  without  a  corresponding  increase  of  their 
enemies  and  serious  damage  results.  Inasmuch  as  these  same 
enemies  attack  the  cabbage-aphis,  Professor  C.  E.  Sanborn  *  has 
suggested  that  the  cabbage-aphis  might  be  encouraged  to  multiply 
on  crops  planted  near  melons  or  cucumbers,  so  that  an  abundance 
of  parasites  and  insect  enemies  might  be  in  readiness  to  attack  the 
melon-aphis  when  it  appears.  This  might  be  done  by  planting 
kale,  rape,  or  wild  mustard  in  the  fall,  upon  which  the  cabbage - 
aphides  will  pass  the  winter  and  will  multiply  in  early  spring. 
This  trap-crop  should  be  planted  in  rows  around  the  prospective 
melon-field,  and  if  the  latter  be  large,  rows  should  be  planted 
through  it.  If  the  kale  does  not  soon  become  infested  with  the 
cabbage-aphis,  transport  some  from  the  nearest  cabbage-patch. 
The  ladybirds  and  parasites  multiply  rapidly  with  plenty  of  the 
cabbage-aphides  for  food,  and  as  soon  as  the  food  supply  becomes 
scarce  they  are  forced  to  migrate  and  will  search  out  any  colonies 
of  melon-aphides. 

Control. — The  most  important  factor  in  the  control  of  this, 
as  well  as  many  other  aphides,  is  constant  watchfulness,  inspect- 
ing the  plants  frequently  and  destroying  badly  infested  individual 
plants  and  treating  small  areas  before  the  pest  becomes  spread 
throughout  the  crop. 

Where  a  few  young  plants  are  affected  or  before  the  leaves  have 
become  badly  curled,  the  aphides  may  be  destroyed  by  spraying 
with  kerosene  emulsion,  containing,  5  to  8  per  cent  kerosene, 
whale-oil  soap,  1  pound  to  5  gallons  of  water,  or  tobacco  extracts. 
Emulsion  must  be  carefully  made  or  burning  will  result.  The 
aphides  must  be  hit  to  destroy  them,  and  it  is  necessary  to  use  an 
underspray  nozzle  (page  75),  or  to  turn  the  vines  over  and  then 
re-turn  them,  so  that  all  the  aphides  may  be  covered.  After 
the  foliage  is  well  curled  it  is  practically  impossible  to  reach  the 
aphides  by  spraying,  and  fumigation  must  be  used. 
*  See  Bulletin  89,  Texas  Agr.  Exp.  Sta.,  p.  44. 


388        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Fumigation  is  inucli  the  most  satisfactory  method  of  destroy- 
ing the  aphides,  for  it  will  kill  them  all  even  though  the  leaves  be 
curled.  Carl:)on  ])isulfide  was  formerly  used  quite  extensively 
for  this  purpose,  a  teaspoonf ul  being  applied  for  each  cubic  foot 
of  space  under  the  tub,  box,  or  cover  used.  Recently,  however,  it 
has  been  shown  that  tobacco-paper  is  a  much  more  satisfactory 
fumigant  and  it  has  been  extensivel}'  used  with  excellent  results. 
A  light  frame  is  made  large  enough  to  cover  the  size  of  plants  to  be 
treated  and  covered  with  cheap  muslin  which  is  sized  with  oil. 
The  cloth  should  extend  on  the  ground  for  about  a  foot,  so  that 
it  may  be  covered  with  earth.  One  man  can  look  after  about 
ten  frames.  After  the  frame  is  placed  over  the  plant  a  sheet 
or  half  sheet  of  the  tobacco-paper  (according  to  the  brand  used 
and  experience  with  it)  is  torn  in  two  and  a  half  placed  in 
perforated  tin  cans  in  opposite  corners  of  the  frame,  and  ignited. 
Earth  is  then  heaped  over  the  flap  and  the  fumigation  should 
continue  ten  to  thirty  minutes,  according  to  the  strength  used, 
and  other  conditions,  as  experience  will  determine.  This  treat- 
ment has  the  advantage  that  it  destroys  all  of  the  aphides  while 
the  predaceous  and  parasitic  insects  are  merely  stupefied  and 
soon  revive  and  feed  on  any  remaining  aphides.  "Fumigating- 
kincl  "  tobacco  powder  might  probably  be  used  instead  of  paper 
and  is  used  very  extensively  for  the  same  purpose  in  fumigating 
green-houses  for  this  pest.  Many  tobacco  preparations  are  on 
the  market  for  greenhouse  fumigation  and  will  usually  be  found 
satisfactory  when  used  as  directed. 

The  Squash-bug  * 

About  the  time  the  vines  begin  to  run  a  wilted  leaf  is  found 
here  and  there  which  examination  shows  to  be  due  to  the  common 
brownish-l)lack  squash-bug.  If  search  be  made  in  early  morning, 
the  bugs  wall  usually  be  found  secreted  under  clods  of  earth,  or 

*  Anasa  tristis  DeG.  Family  Coreidoe.  See  Weed  and  Conradi,  Bulletin 
89,  N.  H.  Agr.  Exp.  Sta.;  F.  H.  Chittenden,  Circular  39,  Div.  Ent.,  U.  S. 
Dept.  Agr. 


INJURIOUS  TO  MELONS,  CUCUMBERS,  SQUASH,  ETC.      389 


Fig.  279.  — Squaah-bugg  an(}  nymphs  ^t  work  on  yoimg  plant — natural  mm. 


390       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


whatever  rubbish  may  be  near  the  vmes.  They  are  -about 
three-quarters  inch  long,  and  too  well  known  to  need  other 
description. 

Life  Historij. — For  the  next  month  or  six  weeks  the  females 
deposit  their  eggs,  mostly  on  the  under  sides  of  the  leaves.  They 
are  oval,  about  one-sixteenth  inch  long,  laid  in  irregularly 
.'^haped  clusters.  When  newly  laid  they  are  pale  yellow-brown, 
but  this  soon  grows  darker,  so  that  the  stage  of  their  development 

may  be  told  by  the  color. 
In  from  six  to  fifteen  days, 
depending  upon  the  tem- 
perature, the  eggs  hatch. 
The  young  nymphs  are 
brilliantly  colored,  the  an- 
tennae and  legs  being  bright 
crimson,  the  head  and  an- 
terior thorax  a  lighter  crim- 
son, and  the  posterior  thorax 
and  abdomen  a  bright  green, 
but  in  a  little  while  the 
crimson  changes  to  a  jet 
black.  The  young  bugs  re- 
main near  each  other,  suck- 
ing the  juices  from  the 
foliage  and  soon  causing  the 
leaves  to  wither.  During 
their  growth,  which  requires 
four  to  five  weeks,  they  moult  some  five  times.  The  adult  bugs 
appear  in  August,  but  in  the  North  they  neither  mate  nor  lay  eggs 
that  season,  but  feed  until  frosts  blacken  the  leaves,  when  they  dis- 
appear into  winter  quarters,  hibernating  along  the  edge  of  wood- 
lands, beneath  leaves,  under  logs,  boards  or  whatever  shelter 
may  be  available.  In  the  South  there  are  probably  two  or  three 
broods  a  year  according  to  the  latitude. 

Control. — The  eggs  are  easily  seen  and  should  be  picked  off 
and  destroyed.    The  adults  cannot  be  killed  by  insecticides,  but 


Fig.  280. — ^Eggs  of  the  squash-bug — en 
larged,     (Photo  by  R.  I.  Smith.) 


INJURIOUS  TO  MELONS,  CUCUMBERS,  SQUASH,  ETC.       391 

the  nymphs  may  be  destroyed  by  spra^'ing  with  kerosene  emulsion. 
The  adult  bugs  may  be  readily  trapped  by  placing  small  pieces 
of  board  or  similar  shelter  near  the  vines,  under  which  they  will 
hide  at  night  and  fiom  which  they  may  be  gathered  in  the  early 


Fig.  281. — The  squash-bug:  a,  ma- 
ture female;  b,  side  view  of  head 
showing  beak;  c,  abdominal  seg- 
ments of  male;  d,  same  of  female; 
a,  twice  natural  size;  b,  c,  d,  more 
enlarged.  (After  Chittenden,  U.S 
Dept.  Agr.) 


Fig.  282. — The  squash-bug:  adult  at 
left,  and  different  stages  of  nymphs 
—  about  Ij  times  natural  size. 
(Photo  by  Quaintance.) 


morning.  Cucuml)ei's  and  melons  may  be  j^rotected  ])y  planting 
early  sctuash  among  them,  as  the  bugs  prefer  the  squash,  from 
which  they  may  be  collected.  Cleaning  up  the  vines  in  the  fall 
is  evidently  of  importance  in  reducing  the  number  which  will 
hibernate. 


The  Squash  Ladybird  * 

Although  almost  all  of  the  ladyljird  beetles  are  exceedingly 
beneficial,  this  species,  with  its  near  relative  the  bean-ladybird 
(page  315,)  are  the  exceptions  which  prove  the  rule,  being  the  only 

*  Epilachna  borealis  Fab.  Family  Cocci nellidce.  See  F.  H.  Chittenden, 
Bulletin  19,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.;  J.  B.  Smith,  Bulletin  94,  N.  J*. 
Agr.  Exp.  Sta. 


392 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


injurioiLS  foiius  with  which  wv  have  to  contend.  Both  the  beetles 
and  larva)  feed  on  the  foliage  of  various  cucurl)s,  but  prefer  that 
of  the  squash.  It  is  an  Eastern  species,  not  being  injurious  west 
of  the  Mississippi  and  being  most  trouljlesome  in  the  Middle 
Atlantic  States.  The  beetle  is  nearly  hemispherical  in  shape, 
slightly  oval,  about  one-third  inch  long,  yellowish  or  reddish- 
brown,  marked  with  seven  black  spots  on  each  wing-cover  and 
four  smaller  ones  on  the  thorax  as  shown  in  Fig.  283. 

Life  History. — The  life-history,  as  given  by  Dr.  Chittenden  for 
the  District  of  Columbia  and  northward,  is  as  follows:     "The 


Fig.  283. — The  squash  ladybiid  {Epilachne  borealif>  Fab.):  a,  larva;  6,  pupa; 
c,  adult  beetle — three  times  natural  size;  (/,  egg — four  times  natural 
size;  e,  surface  of  egg  highly  magnified.  (After  Chittenden,  U.  S. 
Dept.  Agr.) 


insect  hiliernates  in  the  adult  condition  under  l:)ark  or  other 
convenient  shelter  and  appears  abi-oad  sometime  in  May  or 
June.  Egg  deposition  has  been  oljsei'ved  in  the  latter  part  of 
June,  and  there  is  evidence  that  the  eggs  are  deposited  also  much 
later."  The  eggs  are  about  three-tenths  inch  long,  elongate- 
oval,  of  a  yellow  color,  and  laid  in  irregular  clusters  of  from  12  to 
50.  "  They  hatch  in  from  six  to  nine  days,  and  the  larva3  begin  to 
feed  at  once  on  the  leaves,  causing  them  to  wither  and  die."  The 
larva  is  yellow,  with  six  rows  of  ])lack  Ijranching  spines,  and  is 
about  one-half  inch  long  when  grown.  "The  larva  attains  full 
development  in  from  two  to  four  weeks,  ceases  feeding,  and  attaches 


INJURIOUS  TO  MELONS,  CUCUMBERS,  SQUASH,  ETC.      393 


itself  by  its  anal  extremity  to  a  leaf,  and  next  day  sheds  its  larval 
skin,  which  is  pushed  down  toward  the  end  of  the  body,  when  the 
pupa  stage  is  assumed.  The  la  va  matures  anytime  from  the 
middle  of  July  to  near  the  mid- 
dle of  September.  In  the  pupa 
state  the  insect  remains  from 
six  to  nine  days,  when  the  skin 
separates  down  the  back  and 
the  perfect  beetle  emerges, 
the  new  l)ro()d  appearing  as 
early  as  the  hist  of  July. 
After  feetling  for  some  time 
the  beetles  disappear  for  hiber- 
nation, .  .  .  beginning  about 
the  middle  of  September." 
The  adults  have  the  habit  of 
marking  out  a  circular  area 
of  the  leaf,  which  seems  to 
cause  the  tissue  to  wilt,  and 
then  feeding  within  this  area. 
The  larvae  are  to  be  found 
feeding  on  the  under  surface  of 
the  foliage  in  July  and  August. 

Con^roL— Usually  hand  picking  the  l^eetles  and  eggs  will 
control  the  pest,  but  if  abundant  it  may  be  readily  destroyed  by 
spraying  or  dusting  with  arsenicals. 


Fig.  284.— Work  of  the  squash  lady- 
bird— greatly  reduced.  (After  W, 
E.  Britton.) 


The  Squash-vine  Borer  * 

In  many  localities  the  most  serious  pest  of  squash  is  the 
Squash-vine  Borer,  and  although  other  cucurbs  are  sometimes 
injured,  they  are  relatively  free  from  attack  if  squash  or  pumpkins 
are  pres(Mit.     The  larva;  bore  in  the  stems,  causing  them  to  rot 

*  Melittia  sntyriniformis  Hbn.  Family  Scsiidoe.  See  Circular  3S  Bureau 
of  Entomology,    U.  S.  Dept.  Agr.  ' 


394        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

where  affected ,  so  that  they  break  off  and  the  plant  wilts  and  dies. 
The  presence  of  the  borer  is  indicated  by  the  coarse  yellowish 
excrement  which  it  forces  from  its  burrow  and  which  is  found 
on  the  ground  beneath,  and  by  the  sudden  wilting  of  the  leaves. 
Injury  is  most  severe  at  the  base  of  the  vine,  which  gradually 
decays,  so  that  it  is  severed  and  the  whole  plant  dies.  A  half- 
dozen  or  more  larvse  are  often  found  in  a  single  stem,  and  as  many 
as  forty  have  been  taken  from  one  vine,  the  larvse  attacking  all 


Fig.  285. — The  squash-vine  borer  (MeliUia  satyrinijorniis  Hbn.):  a,  male 
moth;  h,  female  with  wing.s  folded  at  rest;  c,  eggs  shown  on  bit  of  stem; 
d,  full-grown  larva  in  vine;  e,  pupa;  /,  pupal  cell — all  one-third  larger 
than  natural  size.     (After  Chittenden,  \].  S.  Dept.  Agr.) 


parts  of  the  vine  and  even  the  petioles  and  large  ribs  of  the 
leaves  when  abundant.  Injury  is  worst  on  Hubbard,  marrow, 
cymlings  and  late  varieties  of  squash. 

The  adult  is  one  of  the  clear-winged  moths  with  a  wing  expanse 
of  about  1\  inches,  the  fore-wings  being  opaque,  dark  olive- 
green  in  color,  with  a  metallic  lustre  and  a  fringe  of  brownish 
black.  The  hind-wings  arc  transparent,  with  a  bluish  reflection, 
and  the  veins  and  marginal  fringe  black.  The  abdomen  is  marked 
with  orange,  or  red,  black  arid  bronze,  and  the  legs  are  bright 
orange,  with  tarsi  black  with  white  bands.  The  species  occurs 
throughout  the  States  east  of  the  Rockies  and  southward  into 
Central  and  South  .\merica. 


INJURIOUS  TO  MEL0N8,  CUCUMBERS,   SQUASH,    ETC.     395 

Life  History. —The  moths  appear  soon  after  their  food-plants 
start  growth,  from  mid-April  along  the  Clulf  Coast  to  June  1st, 
in  New  Jersey,  and  late  June  or  early  July  in  Connecticut.  They 
fly  only  in  the  daytime,  and  their  clear  wings  and  brightly  marked 
bodies  give  them  a  close  resemblance  to  large  wasps.  The  eggs 
are  laid  on  all  parts  of  the  plant,  but  chiefly  on  the  stems,  par- 
ticularly near  the  base.  The  oval  egg  is  of  a  dull  red  color  and 
about    one-twenty-fifth    inch    long.      The    moth    deposits    her 


I  iG.  286.     A  squash  stem  cut  open  showing  borers  within.     (Photo  by  Quain- 

tance.) 


eggs  singly,  and  one  individual  has  been  observed  to  lay  as  many 
as  212.  They  hatch  in  one  or  two  weeks.  The  young  larva  enters 
the  main  stem  and  tunnels  through  it,  and  often  enters  the  leaf- 
petioles  l^ranching  from  it.  It  is  a  soft,  stout ,  whitish  caterpillar, 
with  a  small  black  head,  and  about  one  inch  long  when  full  grown. 
The  larvse  reach  maturity  in  about  four  weeks  and  then  enter 
the  earth,  where  they  make  tough  silken  cocoons,  coated  with 
particles  of  earth,  an  inch  or  two  l^elow  the  surface.  In  the 
South  the  larvae  transform  to  pupae  from  which  a  second  generation 


396        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

of  moths  emerges  in  late  July,  but  in  the  North  the  larvse  hibernate 
in  the  cocoons  over  winter,  and  transform  the  nekt  spring.  The 
pupa  is  about  five-eighths  inch  long,  dark  brown,  and  with 
a  horn-like  process  on  the  head  between  the  eyes.  By  the  aid 
of  this  the  pupa  cuts  open  one  end  of  the  cocoon  and  with  the 
hook-like  spines  on  the  abdomen  wriggles  to  the  surface  of  the 
earth  before  transforming  to  the  moth.  As  indicated,  there  is 
but  one  generation  in  the  North,  a  partial  second  brood  in  the 
latitude  of  New  Jersey  and  the  District  of  Columbia,  and  two 
full  generations  in  the  South. 

Control. — As  the  larvie  work  within  the  vines,  insecticide 
treatment  is  useless,  and  the  pest  nuist  Ije  controlled  by  methods 
of  culture. 

Obviously  the  vines  should  l3c  raked  up  and  destroyed  as 
soon  as  the  crop  is  gathered,  so  as  to  destroy  all  of  the  borers 
within  them.  As  the  larva?  or  pupse  hibernate  over  winter  in 
the  soil,  it  has  been  found  that  frequent  light  harrowing  in  the 
fall  will  bring  them  to  the  surface,  and  that  deep  plowing  in  the 
early  spring  will  then  bury  any  surviving  so  that  the  moths 
cannot  emerge.  Rotation  of  the  crop  will  evidently  decrease  the 
number  of  moths.  Where  the  pest  is  abundant  late  squash  may 
be  protected  by  planting  rows  of  early  summer  squashes  as  soon 
as  possible.  These  will  attract  the  moths  so  that  there  wull  be 
relatively  few  eggs  deposited  on  the  main  crop  planted  later.  As 
soon  as  the  early  crop  is  gathered,  or  as  soon  as  it  becomes  well 
infested,  if  it  is  used  only  for  a  trap,  the  vines  should  be  raked 
up  and  burned  so  as  to  destroy  all  eggs  and  larva).  It  is  well 
to  cover  the  vines  with  earth  one  or  two  feet  from  the  base 
so  as  to  induce  the  growth  of  secondary  roots,  which  will  support 
the  plant  in  case  the  vine  is  severed  lower  down.  The  old- 
fashioned  method  of  slitting  the  vines  with  a  knife  and  thus 
killing  the  borers  is  about  the  only  means  of  destroying  them 
after  they  have  become  established.  The  position  of  a  borer 
may  be  detected  by  the  excrement  extruded  from  its  burrow, 
and  if  the  wound  be  covered  with  moist  earth  it  will  assist  the 
healing. 


INJURIOUS  TO  MELONS,  CUCUMBERS,  SQUASH,  ETC.      397 

The  Pickle  Worm  * 

The  pickle  worm  is  so  callecl  because  it  was  first  noted  as 
injuring  cucuml^ers  grown  for  pickling,  but  in  the  Gulf  States, 
where  it  is  most  injurious  it  is  more  commonly  a  pest  of  melons, 
and,  with  the  following  species,  with  which  it  is  often  confused^, 
is  often  known  as  the  "  melon  worm."  Injury  in  the  Middle 
States  occurs  only  periodically,  though  it  has-  been  noted  in 
Illinois  and  southern  Michigan,  but  in  the  Gulf  States  it  is  always 
a  serious  pest  of  all  the  cucurbs,  destroying  the  blossoms,  mining 
the  stems,  and  boring  into  the  ripening  fruit. 

The  moth  has  a  wing  expanse  of  about  1^  inches,  is  }'ellowish- 
brown  with  a  purplish  iridescence,  and  is  readily  recognized  by 
an  irregular  yellowish  transparent  spot  on  the  middle  of  the 
fore-wings,  and  the  basal  half  of  the  hind-wings  of  the  same  color. 
The  abdomen  terminates  in  a  conspicuous  brush  of  large  blackish 
scales. 

Life  History. — The  moths  emerge  in  late  spring  and  deposit 
the  eggs  either  singly  or  in  clusters  of  3  to  8  on  the  flowers,  buds, 
or  tender  terminals.  The  yellowish-white  egg  is  about  one- 
thirtieth  inch  long,  and  rather  elliptical.  The  first  larvae 
are  to  be  found  in  Georgia  by  the  middle  of  June.  The  young 
larvae  which  hatch  from  eggs  laid  on  the  terminals  bore  into 
stems  and  leaves  and  later  often  tunnel  out  the  vines  like  the 
scjuash-vine  borer.  Those  from  eggs  laid  on  the  blossoms  usu- 
all}'  feed  in  the  blossoms,  and  a  half-dozen  may  often  be 
found  feeding  in  single  squash  l)lossoms,  for  which  they  seem 
to  have  a  decided  preference.  As  they  grow  older  the  larvae 
wander  from  one  plant  to  another,  often  boring  into  several 
fruits.  The  older  larvte  bore  into  the  fruit,  the  excrement 
being  pushed  out  from  the  orifice  and  later  accumulating  in 
the  cavity  within.  A  single  larva  boring  into  the  rind  will  do 
sufficient  injury  to   start  decay  and  ruin  the  fruit,  and  often  a 

*  Diaphania  nitidalis  Cramer.  Family  Pyraustidoe.  See  A.  L.  Quaintance, 
Bulletin  54,  Geo.  Agr.  Exp.  Sta.,  R.  I.  Smith,  Bulletin  214,  N.  C.  Agr. 
Exp,  Sta. 


308 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


half-dozen  or  more  will  be  found  in  a  single  melon.  Until  half 
grown  the  larvse  are  marked  with  transverse  rows  of  black 
spots.     The  full-grown  larva  is  about  three-quarters  inch  long, 


l*'iG.  287. — The  pickle  worm  {Diaphariia  nitidalis  Cramer):   larva,  pupa,  and 
adult — all  enlarged.     (Photos  by  Quaintance.) 

greenish  or  yellowish-green,  with  head  and  prothoracic  shield 
brown.  The  larva  reaches  maturity  in  about  two  weeks,  when 
a  thin  silken  cocoon  is  made  in  the  fold  of  a  leaf  in  which  the 


INJURIOUS  TO   MELONS,  CUCUMBERS,  SQUASH,  ETC.       399 


pupal  stage  is  assumed,  which  occupies  about  a  week.     The  pupa 
is  one-half  to  one  inch  long,  brown,  with  wing  and  leg  sheaths 
lighter^  and  the  tip  of  the  alxlomen  bears  a  group  of  short  curved 
spines  which  hold  the  pupa  more  securely  in  the  cocoon.     During 
July  and  August  the  complete  life  cycle  requires  a])out  four  weeks 
in  Georgia,  and  at  least  three  definite  generations  have  been 
recognized^  the  injury  by  the 
larvae    being    most    severe  in 
July    and    August,   evidently 
by    the     second     generation. 
The   winter   is   passed  in  the 
pupal  stage  in  the  foliage  or 
trash  remaining  on  the  field. 
Control. — As  injury  is  worst 
in  late    summer,  earh'  plant- 
ings   and  early-maturing  va- 
rieties are  but  little  injured. 
The  thorough    destruction  of 
the   vines,   foliage,  and   trash 
on  the   field  after  the  crop  is 
secured  is  of  the  utmost  im- 
portance   in    controlling    this 
as    well    as    other    pests    of 
cucurbs,    and    may    probably 
be     accomplished    with     this 
species     by     deeply    plowing 
under  the  refuse.      Professor 
A.    L.    Quaintance,  to   whom 
we  are  indebted  for  our  knowl- 
edge of   this   pest,  has    found    that  the  moths  greatly  prefer  to 
oviposit  on  squash  and  that  it    may  be  successfully  used  as  a 
trap-crop  for  the  protection  of  other  cucurbs.     Rows  of  summer 
squash  should  be  planted  through  the  cucumber  or  melon  fields 
as  early  as  possible,  the  rows  being  planted  every  two  weeks  so 
there  will  be  flowers  through  July.     The  squash  bloom,  with  the 
contained  larvse,  must  be  collected  and  destroyed  at  frequent 


Fig.  288.— Squash  flower  infested 
with  pickle  worms.  (Photo  by 
Quaintance.) 


400         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

intervals.  Otherwise  the  squash  will  merely  augment  the  injury,  as 
the  larvae  will  migrate  to  the  crop.  Careful  tests  of  this  method 
showed  almost  complete  protection  to  muskmelons.     The  use  of 


Fig.  289. — Pickle  worms  at  work  on  a  cucumber.     (Photo  by  Quaintance.) 

arsenicals  has  been  of  little  value  against  this  pest  as  far  as  tested, 
but  as  they  should  be  applied  to  control  the  next  species,  may  be 
of  some  incidental  value. 


The  Melon  Caterpillar  * 

This  species  is  very  similar  to  the  last  in  life  history  and  habits 
and  is  very  commonly  confused  with  it.  It  seems  to  be  injurious 
only  in  the  Gulf  States,  though  the  moths  have  been  taken  from 
Canada  to  Central  America.  The  moth  is  a  beautiful  insect  with 
wings  of  a  pearly  iridescent  whiteness,  bordered  with  brownish- 
black  and  expanding  about  an  inch.  The  anterior  half  of  the 
thorax  and  head  is  the  same  color  as  the  wing  border,  while  the 
abdomen  is  white,  tinged  with  brownish  toward  the  tip ,  which  is 
surmounted  by  a  Inrush  of  long  dark  scales.  The  larvse  are  very 
similar  to  those  of  the  pickle  worm,  and  the  life  history  so  far  as 
ascertained  seems  to  be  practically  the  same.     The  essential  differ- 

*  Diaphania  hyalinita  Linn.  Family  Pyramtidae.  See  A.  L.  Quaintance, 
Bulletin  45,  Geo.  Agr.  Exp.  Sta.,  p.  42;  R.  I.  Smith,  Bulletin  214,  N.  C 
Agr.  Exp,  Sta. 


INJURIOUS  TO  MELONS,  CUCUMBERS,  SQUASH,  ETC.       401 


once  ill  tlir  Juil)its  of  this  siK'cics  is  tliat  llic  young  larva3  very  com- 
monly feed  on  the  foliage.  Lat(>r 
on  they  mine  into  the  stems  and 
fruit  and  are  readily  confused 
with  those  of  the  last  species. 

Control.— The  fact  that  the 
young  larva?  feed  on  the  foliage 
makes  it  possible  to  destroy 
them  with  arsenicals,  and  by 
spraying  the  young  foliage  with 
arsenate  of  lead  3  pounds  to  the 
barrel,  as  advised  for  the  striped 
cucumber-beetle,  they  should  be  readily  controlled.  The  cultural 
methods  advised  for  the  control  of  the  last  species  will  of  course 
be  equally  applicable  for  this. 


Fi'"-  290.  —  The  melon-worm  moth 
{Diajihania  hyalinita  Linn.) —  en- 
larged.    rPhoto  by  Qiiaintance.) 


Fig.  291. — The  melon-worm — enlarged.     (Photo  by   R.  I.  Smith.) 


CHAPTER  XX 

MISCELLANEOUS  GARDEN  INSECTS 

The  Pale-striped  Flea-beetle  * 

Enormous  numbers  of  the  Pale-striped  Flea-beetles  often 
appear  in  late  June  or  early  July  and  nearly  ruin  the  young  crops 
they  may  attack  before  being  brought  under  control.  Such  out- 
breaks occur  only  periodically,  so  that  usually  the  grower  is  unpre- 
pared to  cope  with  them,  which  is  true  of  the  appearance  of  many 


Fig.  292. — The  pale-striped  flea-beetle  {Systena  blanda  Mels.):  a,  larva; 
fe,  beetle;  c,  eggs;  rf,  sculpture  of  egg;  e,  anal  segment  of  larva  from  side; 
/,  s  me  from  above;  a,  d,  six  times  natural  size;  e,  /,  more  enlarged; 
g,  the  banded  fiea-beetle  {Syslena  tceniata  Say) — six  times  natural  size. 
(After  Chittenden,  U.  S.  Dept.  Agr.) 

of  our  worst  insect  pests.  These  flea-beetles  are  almost  omnivorous 
as  regards  food,  for  although  particularly  injurious  to  corn  and 
tomatoes,  they  have  also  injured  beans,  beets,  potatoes,  egg-plant, 
carrots,  melons  and  other  cucurbs,  turnips  and  other  crucifers, 

*  Systena  blanda  Mels.  Family  Chrysomelidoe.  See  F.  H.  Chittenden, 
Bulletin  23,  n.s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  22;  S.  A.  Forbes,  18th  Report 
State  Ent.  111.,  p.  21. 

402 


miscellanecjus  garden  insects  403 

strawberry,  cotton,  oats,  peanuts,  pear  foliage,  etc.,  and  many  com- 
mon weeds,  so  that  it  may  be  safely  said  that  when  abundant  they 
will  attack  almost  any  crop  at  hand.  The  species  seems  to  occur 
practically  throughout  the  United  States,  but  injuiy  has  been  most 
common  in  the  INIiddle  States  east  of  the  plains. 

The  beetle  is  about  one-eighth  inch  long,  cream-colored,  with 
the  wing-covers  marked  with  three  stripes  of  dull  light-brown, 
and  the  eyes  and  abdomen  are  black.  A  nearly  related  species, 
the  banded  flea-beetle,*  is  verj"-  similar  in  appearance,  the  dark 
stripes  being  expanded  until  it  is  a  polished  black  with  two 
white  stripes  (Fig.  292  6),  and  the  two  species  have  until  recently 
been  commonly  considered  as  identical.  They  are  similar  in  life 
history  and  habits  so  far  as  known,  and  may  be  considered  as 
the  same  for  practical  purposes. 

Life  History. — Ycry  little  is  known  of  the  life  history.  The 
beetles  usually  appear  in  late  June  and  early  July,  coming  out  in 
enormous  numbers,  gnawing  small  holes  in  the  foliage  of  the  plants 
attacked,  so  that  when  abundant  they  completely  defoliate  the 
plant  in  two  or  three  days  and  often  necessitate  replanting.  Dr. 
Chittenden  has  observed  the  eggs,  which  were  deposited  in  the 
District  of  Columbia  from  June  10th  to  July  8th.  The  egg  is  ellip- 
tical, about  one-fortieth  inch  long,  and  light  ])uff-yellow  in 
color.  The  larvae  feed  on  the  roots  of  various  common-weeds, 
including  lambsquarter  and  Jamestown  weed.  They  were 
observed  to  be  full  grown  by  the  middle  of  May  in  central  Illinois 
and  pupated  May  26th,  from  which  beetles  emerged  June  17th. 
The  larva  is  a  whitish,  slender  grub  much  like  those  of  other  flea- 
beetles.  It  is  about  one-eighth  inch  long  when  full  grown,  with 
light-brown  head,  and  the  anal  segment  tapers  to  a  conspicu- 
ous prolonged  process,  surmounted  at  the  apex  by  a  number  of 
stiff,  spiny  hairs.  From  the  data  recorded  it  would  seem  probable 
that  the  insect  winters  in  the  larval  stage  on  the  roots  of  various 
weeds  and  develops  to  the  adult  in  early  summer  when  the 
eggs  are  laid.  There  seems  to  be  no  direct  evidence  of  a  second 
generation. 

*  Systena  taeniata  Say. 


404        INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 

Control. — The  tlest ruction  of  tlic  weeds  on  which  the  larvao 
develop  is  of  obvious  importance,  and  it  would  be  well  to  plow 
under  deeply  any  fields  grown  up  in  weeds  during  late  summer. 
Bordeaux  mixture  is  possibly  the  best  repellant  for  these  beetles, 
though  they  will  be  driven  off  by  covering  the  plants  with  any 
dust  which  thoroughly  coats  the  foliage.  Usually  the  best  method 
will  be  to  spray  the  plants  thoroughly  with  Bordeaux  mixture 
containing  3  pounds  of  arsenate  of  lead  or  one-third  pound  Paris 
green  per  barrel.  All  parts  of  the  foliage  must  be  thoroughly 
coated.  Good  success  has  also  attended  dusting  the  plants  with 
Paris  green  and  flour  and  by  spraying  the  beetles  with  kerosene 
emulsion.  Powdered  arsenate  of  lead  dusted  over  the  foliage 
while  the  dew  is  on  would  probal^ly  prove  effective,  or  it  might  be 
sprayed  at  the  rate  of  3  to  5  pounds  to  the  l^arrel. 

The  Tarnished  Plant-bug  * 

The  tarnished  plant-bug  is  one  of  the  most  common  and 
troublesome  plant-bugs  throughout  the  country  from  Canada  to 
Mexico.  Seemingly  it  is  nearly  omnivorous,  as  it  attacks  almost 
all  of  the  common  garden  crops,  small  fruits,  tender  shoots  of  fruit 
trees  and  young  nursery  trees,  many  flowering  plants,  and  most  of 
our  common  weeds.  Both  nymphs  and  adults  injure  the  plants 
by  sucking  out  the  juices,  and  on  numy  plants  a  small  black  spot 
appears  where  the  insect  has  l^een  feeding,  which  causes  a  deform- 
ation of  the  stem  or  leaf,  as  in  the  "  Ijuttoning  "  of  strawberries, 
or  tends  to  "  blight  "  the  terminal  as  in  the  case  of  dahlias,  pota- 
toes, and  similar  crops. 

The  adult  is  nearly  one-quarter  inch  long,  of  a  l3rassy- 
brown  color,  marked  with  black  and  yellow,  and  the  thorax  with 
red.  The  color  and  markings  are  quite  variable.  The  nymphs 
feed  upon  the  same  plants  as  the  adults  and  pass  through  four 
stages,  shown  in  Fig.  293.  The  first  stage  is  only  one-twentieth 
inch   long  and   yellowish   or  yellowish-green.      The  second  stage 

*  Lygus  pratensis  Linn.  Family  Capsidoe.  See  Stedman,  Bulletin  47, 
Missouri  Agr.  Exp.  Sta. 


MISCELLANEOUS   GARDEN   INSECTS 


405 


is  about  twice  as  large,  and  similarly  colored,  except  that  there  are 
two  pairs  of  dark  spots  on  the  thorax  and  one  on  the  middle  of  the 
third  abdominal  segment,  which  grow  more  distinct  in  the  last  two 
stages.  With  the  third  stage  the  small  wing  pads  become  visible 
and  in  the  fourth  stage  they  extend  halfway  down  the  abdomen. 

Life  History. — The  adults  hil^ernate  over  winter  under  any 
shelter  available,  such  as  the  trash  on  affected  fields,  under 
leaves,  boards,  stones,  etc.,  and  emerge  in  early  spring.  The 
eggs  are  laid  in  Missouri  in  April.     But  little  is  known  of  the 


Fig.  293. — The  tarnished  plant-bug  (Ltjgus  pratensis  Linn.):  a,  b,  c,  d,  four 
stages  of  nymphs;  e,  adult  bug — all  about  four  times  natural  size.  (After 
Forbes  and  Chittenden,  U.  S.  Dept.  Agr.) 


places  of  oviposition,  except  that  Taylor  *  has  shown  that 
sometimes  apples  are  severely  dimpled  l^y  the  egg  punctures. 
It  is  evident,  therefore,  that  the  eggs  are  inserted  in  the  stems 
or  leaves  of  the  food-plants.  The  pale  yellow  egg  is  about 
one-thirtieth  inch  long,  oval,  elongate,  and  flared  at  the 
outer  end,  so  as  to  be  somewhat  bottle-shaped.  The  first  genera- 
tion becomes  full  grown  in  about  a  month,  after  which  all  stages 
*  See  E.  P.  Taylor,  Journal  of  Economic  Entomology,  Vol.  I,  p.  370. 


406       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

may  be  found  feeding  together  until  September  or  October. 
In  southern  Missouri  Professor  Stedman  states  that  there  are 
three  generations,  while  in  northern  Missouri  only  two,  but  the 
exact  number  has  not  been  carefully  determined. 

Control. — This  is  an  exceedingly  difficult  insect  to  control, 
owing  to  the  large  number  of  food-plants  and  the  fact  that  the 
adult  takes  wing  and  flies  off  quickly  upon  the  least  disturbance. 
As  it  sucks  its  food,  arsenical  insecticides  are  of  course  useless, 
and  some  contact  insecticide  must  be  vised  with  which  the  insect 
may  be  hit.  The  nymphs  may  be  sprayed  at  any  time,  but  to 
hit  the  adult  bugs  they  must  be  sprayed  in  early  morning,  while 
still  sluggish.  Spraying  will  be  profitable  where  the  nymphs 
are  abundant,  but  it  is  douljtful  whether  it  will  be  found  a  satis- 
factory means  of  combating  the  adults.  Ten  per  cent  kerosene 
emulsion  and  tobacco  extracts  have  been  used  successfulh'. 
Where  they  are  abundant  the  adults  may  be  collected  in  consider- 
able numbers  by  sweeping  the  foliage  in  early  morning  with  a 
strong  insect  net  and  then  dropping  them  into  kerosene.  Clean 
culture,  including  the  destruction  of  all  weeds,  and  such  vegeta- 
tion or  trash  as  may  furnish  hibernating  quarters,  are  important, 
as  it  is  observed  that  injury  is  always  worse  where  weeds  have 
been  allowed  to  multiply  and  the  ground  has  been  covered  with 
weeds  and  trash. 

The  Garden  Webworm  * 

The  term  garden  webworm  is  possibly  a  misnomer,  for  although 
these  little  caterpillars  frequently  do  more  or  less  injury  to  various 
garden  crops  when  they  become  overabundant  and  migrate  to 
them  from  the  weeds  on  which  they  nomiully  feed,  and  occasionally 
do  some  damage  to  sugar  beets,  they  are  best  known  as  a  pest  of 
corn  and  cotton.  Though  the  species  occurs  throughout  the 
United  States  and  south  to  South  America,  it  has  been  most 
injurious  from  Nebraska  southward  and  cast  to  Mississippi    and 

*  Loxostege  similalis  Gn.  Family  Pyrnustidoe.  See  C.  V.  Riley,  Report 
U.  S.  Comm.  Agr.  for  1885,  p.  265;  Sanderson,  Bulletin  57,  Bureau  of  Ento- 
mology, U.  S.  Dept.  Agr.,  p.  11. 


MISCELIANEOUS  GARDEN   INSECTS 


407 


Illinois.  The  hirvio  feed  uoriually  on  the  pigweed  or  careless 
weed  (Amaranthus  spp.)  from  wliieli  they  sometimes  receive  the 
local  name  of  "  careless  worm,"  and  only  when  they  become 
overabundant  on  these  weeds  do  they  usually  increase  sufficiently 
to  migrate  from  them  and  attack  crops. 

The  moth  is  a  yellowish,  buff  or  grayish-brown  color,  marked 
as  shown  in  Fig.  294,  and  with  a  wing  expanse  of  about  three- 
quarters  of  an  inch.  The  larva  also  varies  in  color  from  pale  and 
greenish-yellow  to  dark  yellow,  and  is  marked  with  numerous 
black  tubercles  as  shown  in  Fig.  294,  b,  c. 

Life  Histonj. — The  hil)ernating  habits  are  not  known,  ])ut  from 
analogy  with  the   beet  webworm,   and   the   appearance   of  the 


Fig.  294. — The  garden  webworm  (Loxostege  similalis  Gn.):  a,  male  moth; 
b,  c,  larvae;  d,  anal  segment  of  same;  e,  abdominal  segment  of  same  from 
side;  /,  pupa;  g,  tip  of  abdomen  of  same;  a,  b,  c,  f,  somewhat  enlarged; 
d,  e,  g,  more  enlarged.     (After  Riley  and  Chittenden,  U.  S.  Dei)t.  Agr.) 

moths,  it  seems  pro])able  that  the  winter  is  passed  Ijy  the  larvae 
or  pupjB  in  the  soil.  The  moths  appear  in  Texas  by  mid-April 
and  in  Central  Illinois  in  late  May  and  early  June.  The"  yellowish 
eggs  are  laid  on  the  foliage  in  small  patches  of  from  S  to  20  and 
in  Texas  hatch  in  three  or  four  days.  The  larva3  of  the  first 
generations  feed  on  weeds  or  alfalfa,  where  it  is  growai,  and  then 
migrate  to  corn  and  cotton  or  garden  truck,  the  former  crops 
being  attacked  when  six  or  eight  inches  high.  In  feeding  the 
caterpillars  spin  a  fine  web,  which  gradually  envelops  the  plant, 
of  which  nothing  is  left  but  the  skeletons  of  the  leaves  w^hen  the 
larvae  are  abundant.  The  larvae  become  full  grown  in  about 
three  weeks  in  summer,  when  they  descend  to  the  soil  and  pupate 


408         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


in  small  silken  cells  on  or  just  Ijelow  the  surface.  The  moths 
emerge  about  eight  days  later,  so  that  in  midsummer  the  com- 
plete life  cycle  occupies  about  a  month.  In  Texas  there  are 
probably  five  generations  a  year,  and  in  Nebraska  and  Illinois 
three  or  four  generations. 

Control. — The  plowing  of  infested  land  in  late  fall  or  winter, 
or  thorough  disking  of  alfalfa  will  be  found  to  largely  control  the 
pest.  Where  it  appears  on  cultivated  crops  it  may  be  readily 
destroyed  by  at  once  spraying  or  dusting  with  Paris  green  or 
arsenate  of  lead.  The  destruction  of  the  weeds  upon  which  it 
feeds  is  obviously  important  in  preventing  the  undue  multiplica- 
tion of  the  pest. 

The  Rhubarb  Curculio  * 

Rhubarb  is  but  little  troubled  with  insect  pests,  but  occasionally 
the  stalks  are  found  with  numerous  punctures  from  which  the 


Fig.  295. — The  rhubarb  curcuUo  {Lixus  concavus  Say):  a,  beetle;  b,  egg; 
c,  newly  hatched  larva;  d,  full  grown  larva;  e,  pupa;  /,  back  view  of 
last  abdominal  segment  of  pupa — all  about  twice  natural  size.  (After 
Chittenden,  U.  S.  Dept.  Agr.) 

juice  exudes.     This  has  been  caused  by  the  feeding  and  oviposi- 
tion    of    a    large    rusty-brown    snout-beetle,    which    is    usually 

*  Lixus   concavus   Say.     Family   Curculionidoe.     See   F.    H.   Chittenden, 
Bulletin  23,  n.  s.,  Division  of  Entomology,  p.  61. 


MISCELLANEOUS  GARDEN  INSECTS  409 

found  on  the  affected  plants.  It  is  about  three-quarters  inch 
long,  and  will  be  readil\'  recognized  from  Fig.  295.  The  beetles 
hibernate  over  winter  and  feed  on  dock,  in  the  stalks  of  which  the 
eggs  are  laid  in  May.  Although  eggs  are  laid  in  rhubarb,  they 
fail  to  hatch  or  the  young  larva?  die.  The  grubs  become  full 
grown  by  midsummer  and  the  beetles  emerge  in  late  summer 
and  feed  a  little  before  entering  hibernation. 

Control. — As  the  beetles  are  sluggish  and  readily  found, 
they  may  be  easily  destroyed  by  handpicking.  Dock  plants 
near  the  rhubarl)  patch  should  Ix^  pulled  amd  destroyed  in  early 
summer  after  the  l^eetles  have  finished  laying  their  eggs. 

The  Celery  or  Greenhouse  Leaf-tyer  * 

This  little  caterpillar  has  become  known  as  the  celery  leaf- 
tyer,  for  although  it  damages  cabbage,  beets,  tobacco,  lettuce, 
cauliflower,  parsley,  cucumber,  sweet  pea,  and  strawberry,  it 
has  been  specially  injurious  to  celery.  It  is  equally  well  known 
as  the  greenhouse  leaf-tyer,  for  it  is  one  of  the  worst  insect  enemies 
of  the  florist,  attacking  violet,  rose,  chrysanthemum,  carnation, 
and  other  greenhouse  plants.  On  celery  the  larva?  both  l^ore 
in  the  stems  and  web  up  the  foliage  upon  which  they  feed  upon 
the  surface,  skeletonizing  the  leaves.  The  usual  method  of 
feeding,  to  which  is  due  the  common  name,  is  to  fasten  together 
two  contiguous  leaves,  to  curl  over  the  edge  of  a  single  leaf,  or 
to  spin  a  thin  silken  web  within  which  to  feed. 

The  moth  resembles  that  of  the  garden  web  worm,  having  a 
wing  expanse  of  about  three-quarters  of  an  inch,  the  fore-wings 
being  light  clay-brown,  suffused  with  reddish  or  ochreous  brown 
and  marked  with  blackish  cross-lines  as  shown  in  the  illustration, 
and  the  hind- wings  are  gray  with  darker  margins.  The  full- 
grown  larva  is  about  three-quarters  inch  long  and  of  a 
translucent  greenish-white  color.     Down  the  middle  of  the  back 

*  Phlyctaenia  rubigalis  Guen.  Family  Pyralidoe.  See  F.  H.  Chittenden, 
Bulletin  27,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.;  M.  V.  Slingerland,  Bulletin 
190,  Cornell  Univ.  Agr.  Exp.  Sta.,  p.  159. 


410         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

is  a  narrow  green  stripe,  which  is  bordered  on  either  side  by  a 
wider  greenish-white  stripe.  The  head  is  dark  straw  color, 
mottled  with  darker,  often  purplish  dots.  The  species  is  widely 
distributed,  occurring  in  practically  all  parts  of  the  United  States, 
and  may  be  readily  introduced  into  greenhouses  upon  plants. 
Life  History. — The  eggs  are  very  much  flattened,  translucent, 
broadly  oval  disks  about  one  thirty-second  inch  long,  laid  in  clus- 
ters of  from  eight  to  twelve,  several  often  overlapping.  The  eggs 
hatch  in  from  five  to  twenty  days,  according  to  the  temperature. 
The  larvffi  feed  mostly  at  night  and  become  full  grown  in  from 


Fig.  296. — The  celery  leaf-tyer  {Phlydania  rubigalis  Hbn.):  a,  moth;  ^>, 
same  in  natural  position  at  rest;  c,  egg  mass;  d,  larva  from  above;  c, 
same  from  side;  /,  head  of  same;  g,  pupa  case;  h,  chrysalis — one-half 
larger  than  natural  size  except  c,  which  is  twice  natural  size,  and  /, 
more  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 


three  to  five  weeks.  They  transform  to  pupse  within  the  webs 
which  they  have  formed  between  the  leaves,  and  the  moths 
emerge  one  or  two  weeks  later.  The  number  of  generations 
which  occur  out  of  doors  and  the  method  of  hibernation  have  not 
been  determined,  but  there  are  probably  at  least  three  generations 
in  the  open,  while  the  number  in  greenhouses  will  depend  upon 
the.  temperature  and  the  food  available. 

Control. — No  very  thorough  experiments  in  the  practical  con- 
trol of  the  pest  on  field  crops  seem  to  have  been  made.  A  thorough 
application  of  arsenate  of  lead  as  soon  as  the  young  larvae  are 
noticed  and  before  they  have  webbed  the  foliage    badly  would 


MISCELLANEOUS   GARDEN   INSECTS 


411 


doubtless  destroy  them,  but  after  they  have  become  estabhshed  in 
their  webs,  handpicking  will  probably  be  the  only  effective  remedy 
on  such  a  crop  as  celery. 


The  Celery  Caterpillar  * 

Everyone  who  grows  celery,  parsley  or  carrots  is  familiar  with 
the  large  black-striped  green  caterpillar  which  feeds  on  their 
foliage,  as  it  is  probably  the  most  common  pest  of  those  plants  in 
all  parts  of  the  country,  ragging  the  foliage  and  attacking  the 
blossoms  and  undeveloped  seeds.     It  is  the  larva  of  our  most 


Fig.  297. — The  celery  caterpillar  {Papilio  polyxenes  Fab.) :  a,  full  grown  larva, 
side  view;  b,  front  view  of  head  showing  extended  osmateria;  c,  male 
butterfly;  d,  egg;  e,  young  larva;  /,  suspended  chrysalis — about  natural 
size  except  d.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

common  black  swallowtail  butterfly,  shown  natural  size  in  Fig. 
297.  The  wings  of  the  male  are  velvety  black  with  bands  of  yel- 
low spots.  On  the  inner  angle  of  the  hind-wing  is  a  well-marked 
eyespot,  and  the  hind-wing  terminates  in  a  distinct  'Hail."  The 
female    is    somewhat   larger,  the   inner   row    of   j^ellow    spots   is 

*  Fdjiihn  jxilji.vcnrs  I'a!).     I'aniily  Pcipilianidcp. 


412         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

wanting,  and  the  hind-wings  are  covered  with  pale-blue  scales 
on  the  posterior  half.  There  is  considerable  variation,  however 
in  the  color  of  both  sexes. 

Life  History. — In  the  North  the  winter  is  passed  in  the  chrysalis 
stage  and  the  butterflies  appear  in  May  in  New  England,  while  in 
the  far  South  the  butterflies  hibernate  over  winter  and  appear  in 
March  or  April.  The  eggs  are  laid  on  the  foHage  and  are  of  globu- 
lar form,  about  one-twenty-fifth  inch  in.  diameter,  at  first 
pale  honey-yellow,  but  later  reddish-brown.  The  eggs  hatch  in 
from  four  to  nine  days.  The  young  larvse  are  quite  dissimilar 
from  the  older  stages,  being  nearly  black  with  a  white  band  around 
the  middk^  of  the  Ijody  (P'ig.  297,  e) .  The  larva?  feed  exclusively 
on  umbelliferous  plants,  including  besides  those  mentioned,  cara- 
way, fennel,  parsnip,  dill,  wild  carrot,  wild  parsnip,  and  other 
weeds  of  this  family.  The  full-grown  larva  is  shown,  natural 
size,  in  Fig.  297,  a.  It  is  bright  green,  sometimes  yellowish,  and 
marked  with  rings  and  spots  of  velvety  black  as  illustrated.  Just 
back  of  the  prothorax  is  a  pair  of  membranous  yellow  horns  called 
osmateria,  which  give  ofT  a  peculiar  pungent  odor,  which  is  quite 
disagreeable  and  evidently  aids  in  frightening  away  enemies. 
These  osmateria  are  soft,  retractile  organs,  which  are  drawn  back 
between  the  segments  and  are  extruded  only  when  the  larva  is 
disturbed. 

In  the  far  South  the  larva  will  become  grown  in  ten  days,  but 
in  the  North  it  requires  three  to  four  weeks.  The  caterpillar 
then  attaches  itself  to  some  part  of  the  plant  by  the  anal  prolegs, 
and  fastens  a  strong  loop  of  silk  around  the  thorax,  and  sheds  its 
skin,  leaving  the  chrysalis  or  pupa  firmly  attached  to  the  leaf  or 
stem  as  shown  in  Fig.  297,  /.  The  chrysalis  is  a  dull  gray  color 
marked  with  black  and  brown  and  about  \\  inches  long.  In  from 
ten  days  to  two  weeks  the  butterfly  emerges  from  the  chrysalis. 
Thus  the  complete  Hfe  cycle  may  be  passed  in  twenty-two  days  in 
the  South  to  eight  weeks  in  the  North.  In  the  North  there  are 
but  two  generations  a  year,  while  in  the  South  there  are  probaloly 
three  or  four. 

Control. — The  caterpillars  ar(?  so  readily  seen,  and  if  nf)t  seen 


MISCELLANEOUS  GARDEN   INSECTS 


413 


they  soon  reveal  their  presence  by  the  pecuHar  odor  when  dis- 
turbed, that  they  may  usually  be  picked  off  and  crushed,  and  so 
rarely  become  sufficiently  numerous  to  waiTant  other  treatment. 
Ihey  may  be  readily  controlled  by  spraying  or  dusting  with 
arsenic  als. 

The  Celery  Looper  * 

This  species  is  very  closely  related  to  the  cabbage  looper  (page 
361)  and  occurs  throughout  the  Northern  States  east  of  the  Rocky 
Mountains.  According  to  Forl:)es  and  Hart  it  is  more  common 
than  the  cabbage  looper  in  Illinois,  where  it  is  a  serious  pest  of 
celery  and  has  been  reared  on  sugar-beet,  but  elsewhere  it  is  not 
as  common. 

The  moth  has  a  wing  expanse  of  about  two  inches,  the  fore- 
wings  being  purplish  brown  with  darker  shades  of  velvety  brown 


Fig.  298. — The  celery  looper  {Plusia  simplex  Guen.):  male  moth  and  larva — 
somewhat  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

and  with  a  prominent  silvery  white  discal  spot,  while  the  hind- 
wings  are  yellowish,  strongly  ]:)anded  with  dark  fuscous.  The 
caterpillar  or  larva  is  similar  to  that  of  the  cabbage  looper,  but  the 
spiracles  are  surrounded  with  black  rings,  while  in  the  cabbage 
looper  these  rings  are  indistinct  or  wanting. 

Forbes  and  Hart  believe  that  there  are  three  broods  in  a  year. 
"  The  caterpillars  of  the  first  generation  of  the  year  hatch  late  in 
May  and  get  their  growth  late  in  June  or  early  in  July.  The  life 
of  the  second  generation  extends  from  the  first  part  of  July  to  the 

*  Plusia  simplex  Guen.  Family  Noctuidoe.  See  Chittenden,  Bulletin  .33, 
Division  of  Entomology,  U.  S.  Dept.  Agr.,  p.  73. 


414  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

niicldk'  of  8('i)teuilx'r,  and  the  tliird  begins  to  issue  from  the  egg 
early  in  October.  This  brood  hibernates  about  half  grown,  attain- 
ing full  size  during  the  latter  part  of  April." 

Control. — No  accounts  of  experiments  in  control  are  on  record, 
but  doubtless  the  same  measures  as  used  against  the  cabljage 
looper  will  l)e  found  applica])le. 


The  Carrot-beetle  * 

The  carrot-beetle  is  a  native  species  which  has  been  particu- 
larly injurious  to  carrots  along  the  Atlantic  Coast  from  Long 
Island  through  the  Gulf  States.  The  species  occurs,  however, 
very  generally  throughout  the  country  as  far  north  as  central 
Indiana,  and  on  the  Pacific  coast.     It  has  a  considerable  number 

of  food-plants;  in  Louisiana 
and  Mississippi  it  has  injured 
the  corn  crop,  the  beetles  cut- 
ting the  corn  just  above  the 
roots;  in  Illinois  the  beetles 
injured  sunflowers  and  sweet 
potatoes;  in  Indiana  they  at- 
tacked carrots,  celery  and  par- 
snips; in  Texas  they  have 
injured  potatoes  and  shrubs 
and  vegetables  of  various 
kinds;  and  in  Nebraska  they 
have  damaged  sugar-beets. 

The  damage  is  done  entirely 
by  the  adult  beetles ,  which  are 
among  the  smaller  of  the  May- 
beetles  or  June-bugs,  measure 
one-half  to  five-eighths  of  an  inch  long,  and  are  from  reddish 
brown  to  nearly  black  in  color.  The  beetles  gouge  into  the  roots 
or  stems  just  below  the  surface  of  the  soil,  often  ruining  the  root 
for  market  without  injuring  the  top.     The  injury  may  occur  by 

*  Ligyrus  gibbosus  Dej.  Family  Scaraboeidoe.  See  F.  H,  Chittenden, 
Bulletin  3:^,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  32. 


Fi(i.  29U. — TIr-  carrut-beetle  (Ligyrus 
gibbosufi  Dej.)  —  much  enlarged. 
(After  Forbes.) 


MISCELLANEOUS  GARDEN   INSECTS  4L5 

hibernated  beetles  in  the  spring  from  April  to  June  or  by  newly 
transformed  individuals  in  late  summer  or  autumn. 

The  life  history  has  not  been  studied,  luit  is  probably  very 
similar  to  that  of  Lachnosterna  (page  79) . 

Control. — No  very  satisfactory  means  of  control  have  been 
tried  in  a  practical  way.  It  is  stated  that  lime  scattered  over 
infested  fields  has  driven  the  Ijeetles  away.  It  is  evident  that 
after  the  crop  is  gathered,  infested  fields  should  be  pastured  with 
hogs,  if  possible,  or  plowed  deeply,  and  plowed  again  in  the  spring. 
Evidently  further  study  of  th(>  habits  of  the  pest  is  necessary  before 
satisfactory  means  of  control  may  be  devised. 

The  Carrot  Rust-fly  * 

The  Carrot  Rust-fly  is  a  European  species,  being  a  serious 
pest  of  carrots  in  England  and  Germany,  which  has  been  known 
in  Canada  since  1885  and  appeared  in  New  York  in  1901  and  since 
then  in  New  Hampshire.  The  larva  or  maggot  which  does  the 
injury  very  much  reseml)les  the  cheese  maggot  or  skipper  in^-en- 
eral  appearance,  is  a  rather  dark  brown,  and  a  little  less  than  one- 
third  inch  long.  The  parent  fly  is  about  one-sixth  inch  long 
with  a  wing  expanse  of  three-tenths  inch,  and  is  a  dark  blackish- 
green  color,  sparsely  clothed  with  yellow  hairs,  and  with  pale 
yellow  head  and  legs,  except  the  eyes,  which  are  black. 

"  Attack  on  carrots  is  not  difficult  of  recognition.  The  leaves 
of  the  young  plants  early  in  the  spring  turn  reddish,  and  the  roots 
are  found  to  be  blotched  with  rusty  patches,  particularly  toward 
their  tips.  The  roots  when  stored  for  winter,  although  not  always 
manifesting  any  degree  of  injury  on  the  outer  surface,  may  at 
times  be  perforated  in  all  directions  by  dirty  Ijrownish  burrows, 
from  which  the  whitish  or  yellowish  larvae  may  be  found  some- 
times projecting."  Celery  is  also  attacked,  the  larva?  eating  the 
thick  part  of  the  root  when  it  is  half  grown,  stunting  the  plant  so 
as  to  make  it  worthless  for  market.     The  life  history  of  the  species 

*  Psila  rosoe  Fab.  See  Chittenden,  Bulletin  33,  n.  s..  Division  of  Ento- 
mology, U.  S.  Dept.  Agr.,  p.  26. 


416         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

does  not  seem  to  have  been  carefully  ol)scrvcd,  ))ut  from  analogy 
is  probably  somewhat  similar  to  that  of  the  cabbage  root-maggot, 
except  that  the  maggots  of  the  carrot  rust-fly  develop  and  trans- 
form on  carrots  in  storage  if  the  temperature  be  sufficient. 

Control. — Late  sowing  has  been  practiced  to  advantage,  and 
the  rotation  of  crops  is  of  obvious  importance,  as  is  the  deep  plow- 
ing of  infested  land.  Where  carrots  have  been  stored  in  earth,  this 
earth  into  which  the  larvae  have  entered  and  pupated  should  be 


Fig.  300. — The  carrot  rust-fly  {Psila  rosae  Fab.):  cf ,  male  fly;  9  ,  female  fly, 
side  view;  a,  antenna  of  male;  b,  full-grown  larva  from  side;  c,  spiracles 
of  same;  a,  anal  extremity  from  (he  end;  e,  puparium;  /,  young  larva; 
g,  anal  segment  from  the  side — eight  times  natural  size  except  a,  c,  d,  g, 
more  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 


treated,  either  by  burying  it  deeply,  spreading  it  out  in  thin  layers 
on  the  surface,  or  throwing  it  into  pools  where  it  will  be  frozen. 
Kerosene  emulsion,  1  part  stock  solution  to  10  of  water  sprayed 
along  the  rows  while  the  carrots  are  young,  or  sand,  land  plaster 
or  ashes,  to  3  gallons  of  which  1  pint  of  kerosene  has  been  added, 
sprinkled  along  the  rows,  have  been  of  some  value  in  Canada. 
These  should  be  applied  three  or  four  times,  once  a  week  after  the 
roots  begin  to  form,  and  particularly  after  the  rows  have  been 
thinned. 


MISCELLANEOUS  GARDEN  INSECTS 


417 


The  Parsnip  Webworm  * 

The  Parsnip  Webworm  is  (juite  a  common  pest  of  the  forming 
seed  of  the  parsnip,  but  fortunately  it  seems  to  prefer  wild  carrot 
as  a  breeding  plant.  It  is  an  imported  species,  occurring  in  north- 
ern Europe,  which  was  first  observed  in  this  country  in  1873  and 
since  then  has  l^ecome  generally  distributed  over  the  Northern 
States  and  Canada  westward  to  the  Mississippi. 

The  moth  is  a  grayish-buff  or  pale  ochreous  color,  marked  with 
fuscous,  the  wings  expanding  about  three-quarters  of  an  inch. 
The  larva  is  a  pale  yellowish,  greenish  or  bluish-gray,  with  con- 


FiG.  301. — The  parsnip  webworm  (Depressnria  heracliana  Do  C\.):  a,  moth; 
b,  c,  larvae;  (/,  pupa;  e,  anal  extremity  of  jjiipa;  /,  umbel  of  parsnip 
webbed  together  by  the  larva} — natural  size.     (After  Riley.) 


spicuous  black  tubercles,  the  head  and  prothoracic  shield  black, 
and  is  about  half  an  inch  long  when  grown.  The  larva?  web  the 
flower-heads  together  until  they  are  contracted  into  masses  of 
web  and  excrement  as  shown  in  the  illustration.  "  After  the 
larvae  have  consumed  the  flowers  and  unripe  seeds  and  become 
nearly  full  grown,  they  enter  the  hollow  stems  of  the  plant  by  bur- 
rowing their  way  inside,  generally  at  the  axils  of  the  leaves,  and 
then  feed  upon  the  soft,  white  lining  of  the  interior.  Here,  inside 
the  hollow  stem,  they  change  to  the  pupa  state.     The  larvae  are 


*  Depressaria  heracliana  DeG. 
"  Ihsect  Life,"  Vol.  I,  p.  94. 


Family  (Ecophoridce.      See  C.  V.  Riley, 


418         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

moderately  gregarious.  They  will  sometimes  cat  newly  sown 
parsnip  after  the  older  plants  originally  attacked  have  been 
destroyed,  in  such  cases  eating  the  tender  green  leaves,  while  of  the 
older  plants  they  eat  only  the  flower-heads  and  interior  lining  of 
the  stems."     The  moths  appear  in  late  July  and  early  August. 

Control. — Thorough  spraying  or  dusting  with  arsenicals  will 
destroy  the  caterpillars,  according  to  Chittenden.  If  the  flowers 
are  destroyed  before  they  are  noticed,  cut  off  and  burn  all  infested 
stems  before  the  moths  emerge  from  the  pupae.  Obviously  it  will 
be  important  to  avoid  planting  parsnips  in  or  near  waste  places 
which  have  grown  up  in  wild  carrot. 

The  Onion  Thrips  * 

The  small  yellowish  "  thrips  "  which  chafe  the  epidermis  from 
the  green  leaves,  causing  them  to  dry  out,  whiten  and  die,  have 
become  well  known  to  onion  growers  in  practically  all  parts  of  the 
United  States  where  onions  are  raised  extensively.  It  is  a  Euro- 
pean insect,  occurring  in  Germany  and  Russia,  and  has  also  been 
imported  into  the  Bermudas. 

The  adult  thrips  is  about  one-twenty-fifth  of  an  inch  long,  of  a 
pale  yellow  color,  tinged  wdth  blackish.  The  general  appearance, 
much  enlarged,  is  shown  in  Fig.  302.  The  slender,  elongate  body 
bears  two  pairs  of  narrow,  bristle-like  wings  which  are  of  no  value 
for  flight.  The  fore-wing  contains  two  wing-veins,  and  the  hind- 
wing  but  one,  the  posterior  margin  of  both  bearing  a  fringe  of  long 
hairs.     When  at  rest  the  wings  lie  together  along  the  back. 

The  thrips  belong  to  a  quite  distinct  order  of  insects,  the 
Thi/sanoptera  (or  Physapoda),  species  of  which  are  commonly 
found  in  the  flowers  of  the  rose  and  clover.  The  mouth-parts  arc 
quite  different  from  those  of  any  other  order  of  insects,  being 
intermediate  between  those  of  biting   and   sucking  insects,   the 

*  Thrips  tabaci  Lind.  Order  Thysanoptera.  See  Quaintance,  A.  L., 
Bulletin  46,  Fla.  Agr.  Exp.  Sta.,  "  The  Strawberry  Thrips  and  the  Onion 
Thrips."  Full  account  and  Bibliography;  Pergande,  Th.,  "  Insect  Life," 
Vol.  VII,  pp.  292-295;  Osborne-Mally,  Bulletin  27,  Iowa  Agr.  Exp.  Sta., 
pp.  137-142;  Sirrine,  Bulletin  83,  N.  Y.  Agr.  Exp.  Sta.,  pp.  680-683. 


MISCELLANEOUS    GARDEN   INSECTS 


419 


mandibles  being  reduced  to  bristle-like  struetui'es.  Their  man- 
ner of  feeding  does  not  seem  to  be  clearly  understood,  though 
Professor  Quaintance  states  that  the  onion  thrips  frequently 
rasps  off  and  swallows  pieces  of  leaf  tissue.  However,  they  are 
able  to  destroy  the  surface  tissue  of  the  leaf  so  that  it  wilts, 
and  fields  badly  affected  become  blighted  and  white. 

This  species  has  quite  a  list  of  food-plants,  cabbage  and  cauli- 
flower often  being  considerably  injured.     Among  them  may  be 


EiG.  302. — The  onion  thrips  {Thrips  tabaci  Lind.)— very  g;reatly  enlarged. 
(Photo  by  Quaintance.) 


mentioned  turnip,  kale,  sweet  clover,  squash,  cucumber,    melon, 
parsley,  tomato,  and  several  common  garden  flowers  and  weeds. 

Life  History. — The  eggs  are  slightly  less  than  Vioo  of  an  inch 
long — too  small  to  be  visible  to  the  unaided  eye — elongate,  and 
curved  somewhat  kidney-shaped.  They  are  laid  singly  just 
beneath  the  surface  of  the  leaf  and  hatch  in  about  four  days. 
The  young  nymphs  resemble  the  adults  in  shape,  but  are  at 
first  almost  transparent  in  color  and  then  a  greenish-j'ellow. 
They  are  frequently  found  feeding  in  small  groups.     Both  the 


420        INSECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 

young  and  adults  have  a  pair  of  sharp  sjjincs  at  the  tip  of  the 
abdomen  which  they  use  to  drive  away  enemies  by  striking  them 
quickly  right  and  left.  Two  or  three  days  after  birth  the  skin  is 
shed  and  another  molt  occurs  five  or  six  days  later.  With  the 
third  stage  the  wing-pads  appear.  This  stage  lasts  four  days^ 
and  during  it  the  insects  take  no  food  and  remain  almost  quiet, 
moving  with  difficulty.  On  onions  the  nymphs  have  been  found 
mostly  on  the  bulbs  in  the  loose  soil.  With  the  next  molt,  the 
insect  becomes  mature  and  winged.  Thus,  the  total  life  cycle  as 
observed  by  Professor  Quaintance  in  Florida  is  about  sixteen  days. 
In  Russia  Dr.  Lindeman  found  that  a  generation  required  forty- 
seven  days.  "  In  Florida  there  are  probably  no  distinct  broods, 
as  all  stages  may  be  found  at  the  same  time.  Allowing  for  the  life 
cycle  at  sixteen  days,  a  large  number  of  broods  could  occur  during 
the  year,  but  unfavorable  conditions  keep  them  reduced,  except 
during  the  spring  and  perhaps  early  summer  (the  worst  injury 
occurring  in  May  and  June),  so  that  it  will  probably  not  happen 
that  they  will  develop  throughout  a  year  according  to  their  capa- 
bilities." 

Control. — The  pest  may  be  successfully  controlled  by  spraying 
with  whale-oil  soap,  1  pound  to  2  gallons  of  water,  rose-leaf  insec- 
ticide, 1  pint  to  4  gallons  of  water,  or  kerosene  emulsion  diluted 
S  to  10  times.  Tobacco  decoction  (see  page  55)  will  pro]3al)ly 
prove  equally  effective,  using  it  as  strong  as  necessary.  Probably 
1  pound  of  stems  to  2  gallons  of  water  will  be  satisfactory.  The 
spraying  should  be  done  very  thoroughly  so  as  to  reach  the  insects 
in  the  axils  of  the  leaves,  and  the  soil  around  the  plant  also  should 
be  well  wet  to  destroy  the  mature  nymphs  that  may  be  hiding. 

The  Imported  Onion-maggot  * 

The  common  white  maggot  which  bores  into  the  roots  and 

bulbs   causing  them  to  wilt  and  decay,    is  probably  the   mo^ 

important  insect  pest  of  the  onion.     The  present  species  is  by  far 

the  most  commonly  injurious  and  is  termed  "  imported  "  because 

*  Pegotnyia  ceparum  Bouche.  Family  Anthomyiidoe.  See  same  references 
as  for  cabbage-maggot,  footnote,  page  347. 


Fig.  303. — The  imported  onion-maggot  {Pegomyia  ceparum  Bouche):  a, 
adult;  b,  maggot;  c,  puparium;  d,  anal  segment  of  maggot  showing 
spiracles;  e,  head  with  mouth-parts — all  very  much  enlarged;  /  and  g 
show  injury  to  young  onions.     (After  J.  B.  Smith.) 


421 


422     INSECT  PESTS  OP^  FARM,  GARDEN  AND  ORCHARD 

it  was  early  known  as  a  post  in  Europe  and  was  imported  into 
this  country  probably  in  colonial  times. 

These  maggots  are  the  offspring  of  small  flics,  somewhat 
resembling  small  houseflies  and  very  similar  to  those  of  the  cabbage 
root-maggot  (see  page  347).*  The  wings  expand  about  three- 
eighths  of  an  inch  and  the  body  is  half  that  long.  The  male  is 
gray  with  black  bristles  and  hairs,  the  face  is  white  with  black 
hairs,  there  are  three  black  lines  between  the  wings,  and  the  abdo- 
men bears  a  row  of  black  spots  along  the  middle.  The  female  is  a 
little  larger,  inclined  to  dark  yellowish,  and  with  a  yellowish  face. 

Life  History. — The  flies  appear  in  the  spring  by  the  time  young 
onions  are  up  and  the  eggs  are  deposited  in  the  sheath  and  in  the 
axils  of  the  leaves,  from  two  to  six  being  placed  upon  a  plant.  The 
eggs  are  just  perceptible  to  the  eye,  white,  oval,  and  about  one- 
twenty-fifth  of  an  inch  long.  The  young  maggot  works  its  way 
down  from  the  sheath  to  the  root,  upon  which  it  feeds  until  it  is 
consumed,  only  the  outer  skin  remaining,  and  often  cuts  off  the 
plant  completely.  Another  plant  is  then  attacked  and  often  sev- 
eral young  plants  are  consumed  l^efore  the  maggot  is  full  grown. 
Later  in  the  season  the  maggots  bore  into  the  bulbs,  a  number  of 
maggots  usually  being  found  in  a  single  bulb  and  their  presence 
being  indicated  by  a  slimy  mass  of  soil  at  the  entrance  of  the 
cavity.  If  such  bulbs  are  not  killed  outright,  they  usually  rot  in 
storage.  The  first  presence  of  the  pest  is  indicated  by  the  wilt- 
ing of  the  young  plants,  and  by  the  central  leaves  of  the  older 
plants  yellowing  and  dying. 

The  maggots  becoma  full  grown  about  two  weeks  after  hatch- 
ing and  are  then  about  three-eighths  of  an  inch  long.  They  are 
dull  white,  with  the  jaws  appearing  beneath  the  skin  as  a  short 
black  stripe  at  the  pointed  end  of  the  body.  The  posterior  end  of 
the  body  is  obtuse  and  is  cut  off  obliquely,  the  margin  of  the  last 
segment  bearing  a  number  of  tubercles  by  which  this  species  may 
l)e  distinguished  from  the  cabbage-root  maggot.  (See  Shnger- 
land,  1.  c). 

*  See  Slingerland,  Bulletin  78,  Cornell  Agr.  Exp.  Sta.,  p.  495,  for  characters 
distinguishing  these  two  species. 


MISCELLANEOUS  GARDEN  INSECTS  423 

The  outer  skin  of  the  maggot  now  brconies  hardened  and 
within  it  the  insect  transforms  to  the  pupa,  which  remains  in  the 
soil  at  the  base  of  the  phint  for  about  two  weeks,  when  the  adult 
fly  emerges.  Two  or  three  gen?rations  probably  occur  in  the 
Northern  States.  Professor  R.  H.  Pettit  states  that  some  of  the 
flies  hibernate  while  many  of  the  pupae  remain  in  the  soil  over 
winter  and  the  flies  issue  from  them  in  the  spring.  This  com- 
plicates remedial  measures. 

Control. — Liberal  applications  of  commercial  fertilizers  such  as 
nitrate  of  soda,  which  will  assist  to  rapid  growth,  are  of  great  value 
in  overcoming  injur}- by  all  root-feeding  pests.  Thorough  culture 
is  of  value.  Rotation  of  the  onion  plot  to  a  point  far  distant 
from  that  of  the  previous  year,  the  cleaning  up  of  old  beds,  and 
plowing  them  deeply  in  the  fall,  will  aid  in  the  control.  Pull  up 
and  destroy  the  young  plants  affected  as  soon  as  noticed,  being 
careful  to  dig  up  the  maggots  with  the  roots.  The  application  of 
carbolic  emulsion  as  for  the  cabbage-root  maggot  has  been  advo- 
cated and  will  doubtless  lessen  the  injury  by  repelling  the  adult 
flies.  Concerning  it  see  page  354.  Apply  early  in  the  season  and 
at  intervals  of  a  week. 

The  Barred-winged  Onion-maggot  * 

The  adult  flies  of  this  species  may  freciuently  be  found  upon 
corn  and  are  readily  recognized  by  the  l)anded  wings.  They  are 
similar  in  size  to  the  last  species,  but  the  back  is  metallic  l)Iue-green 
except  the  head,  which  is  mostly  hoary,  with  brownish-l^lack  eyes. 
The  maggots  have  been  recorded  as  injurious  to  corn  and  sugar- 
cane and  have  been  recently  noted  in  Michigan  associated  with 
the  common  onion-maggot,  destroying  onions. f  The  maggots 
are  similar  to  the  onion-maggot  but  the  posterior  end  is  more 
rounded  and  may  be  distinguished  from  the  illustrations.  The 
winter  is  passed  in  the  puparium  as  far  as  observed. 

Remedies. — In  addition  to  the  measures  advocated  for  the  last 

*  Choetopsis  aenea  Wied.     Family  Anthomyidoe. 

t  See  Pettit,  Bulletin  200,  Mich.  Agr.  Exp.  Sta.,  p.  200. 


424         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

species,  the  destruction  of  the  affected  onions  and  the  thorough 
plowing  of  affected  land  in  the  fall  is  of  prime  importance.     Stored 


au. 


Fig.  304. — The  barred-winged  onion-maggot  {Chatopsis  cenea  Wied.):  a, 
larva,  with  spiracular  opening  highly  magnified  at  left;  h,  puparium; 
c,  adult  fly — all  enlarged.     (After  Riley  and_Howard,  U.  S.  Dept.  Agr.) 

onions  which  prove  infested  may  be  fumigated  with  carbon  bisul- 
fide to  destroy  the  maggots  and  puparia  and  prevent  the  emergence 
of  the  adults. 

The  Asparagus-beetle  * 

This  is  a  well-known  pest  of  asparagus  in  Europe  and  was  first 
observed  in  Queens  County,  New  York,  in  18G2,  where  it  threatened 
to  destroy  the  asparagus,  one  of  the  most  valued  crops  of  the  Long 
Island  truckers.  Since  then  it  has  gi-adually  spread  northward  to 
southern  New  Hampshii'e,  south  to  North  Carolina,  and  west  to 
Illinois  and  Wisconsin,  and  has  been  found  at  two  points  in  Cali- 
fornia. There  seems  no  reason  why  it  should  not  spread  to 
wherever  asparagus  is  grown,  at  least  in  the  Northern  States. 

The  beetle  is  a  handsome  little  creature  about  'one-quarter 
inch  long,  blue-black  in  color,  with  red  thorax,  and  dark  blue 
wing-covers,  marked  with  lemon-yellow  and  with  reddish  borders. 
The  markings  of  the  wing-covers  are  quite  variable,  the  light  color 

*  Crioceris  asparagi  Linn.  Family  Chrysowelidoe.  See  F.  H.  Chittenden, 
Yearbook,  U.  S.  Dept.  Agr.,  1S96,  p.  341;  Bulletin  66,  Bureau  of  Ent.,  pp. 
6,  93,  and  Circular  102,  Ibid. 


MISCELLANEOUS    GARDEN   INSECTS 


425 


sometimes  forming  submarginal  spots,  while  in  otluu'  specimens  it 
becomes  so  diffused  as  to  form  the  principal  color  of  the;  wing- 
covers. 

Both  adults  and  larva)  feed  upon  the  tender  asparagus  shoots 
in  the  spring  and  later  attack  the  fruiting  plants.  Their  attacks 
render  the  shoots  unfit  for  market  and  in  many  cases  their  injury 
has  been  so  severe  as  to  make  it  extremely  difficult  to  establish 
new  beds. 

Life  History. — The  beetles  hibernate  over  winter  under  what- 
ever rubbish  or  shelter  may  be  available  near  the  asparagus  patch. 


Fig.  305. — The  asparagus-beetle  (Crioceris  asparagi  Linn.):  eggs,  larva,  and 
beetle — all  much  enlarged.     (Photos  by  W.  E.  Britton.) 

About  the  season  that  cutting  asparagus  for  market  commences 
they  appear  and  lay  the  eggs  for  the  first  new  brood.  The  egg  is 
dark  brown,  oval,  nearly  one-sixteenth  of  an  inch  long  and  is  laid 
on  end.  The  eggs  are  deposited  upon  the  stems  or  foliage,  usually 
two  to  seven  or  more  in  a  row.  They  hatch  in  from  three  to  eight 
days.  The  young  larvae  at  once  commence  to  attack  the  tender 
shoots,  and  later  in  the  season  feed  upon  the  foliage.  They  become 
full  grown  in  from  ten  day's  to  two  weeks.  The  full  grown  larva,  as 
shown  in  the  illustration,  is  a1)out  one-third  of  an  inch  long,  soft 


426  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

and  fleshy,  much  wrinkled,  and  of  a  dark  gray  or  ohve  color, 
with  black  head  and  legs.  The  mature  larva  drops  to  the  ground 
and  just  beneath  the  surface  forms  a  little  rounded  earth-covered 
cocoon  within  which  it  changes  to  the  pupa,  from  which  the 
beetle  emerges  in  about  a  week.  Thus  the  complete  life  cycle 
may  be  passed  in  a  minimum  of  three  weeks  at  Washington,  D.  C, 
where  there  are  possibly  four  generations  in  a  year,  while  further 
north,  six  or  seven  weeks  may  be  required  for  the  life  cycle,  and 
there  are  probably  only  two  generations. 

The  asparagus-beetles  are  held  in  check  by  several  natural 
agencies.  Several  species  of  ladybird-beetles  feed  upon  the  eggs, 
while  numerous  soldier-l^ugs  attack  the  larvic  which  they  impale 
on  their  stout  beaks.  The  adult  beetles  are  often  killed  by  low 
temperature  in  the  winter,  which  doubtless  limits  their  northern 
spread,  while  the  eggs  and  larva?  are  sometimes  killed  by  the  intense 
heat  of  summer,  which  will  also  probably  limits  the  southern 
spread  of  the  species. 

Control. — One  of  the  best  means  of  control  is  to  keep  all  shoots 
cut  down  in  the  spring  so  as  to  force  the  l^eetles  to  lay  their  eggs 
on  the  young  shoots,  which  are  cut  for  market  every  few  days 
before  the  eggs  have  hatched,  and  hence  no  larva  are  allowed 
to  hatch. 

Another  method  which  has  proven  effective  is  to  cut  down  all 
the  seed  stems  but  a  few  rows  here  and  there,  so  that  the  Iwctles 
will  concentrate  upon  them,  and  then  poison  these  thoroughly 
with  arsenicals,  or  they  may  be  cut  down  and  burned  and  other 
rows  allowed  to  grow  as  traps. 

Air-slaked  lime  dusted  on  the  plants  in  the  morning  while  the 
dew  is  on  will  destroy  the  soft-bodied  larvae  very  effectively. 
Another  way  to  destroy  the  larvte  in  hot  weather  is  to  simply  brush 
them  from  the  plants  so  that  they  will  drop  on  the  hot  soil.  As 
they  crawl  but  slowly  few  will  regain  the  plants,  particularly  if  the 
brushing  be  followed  with  a  cultivator. 

Pro]:)ably  the  most  effective  means  of  controlling  this  pest, 
which  was  formerly  a  very  difficult  one  to  combat,  is  spraying  with 
arsenate  of  lead.     Use  3  pounds  to  50  gallons,  to  which  3  pounds 


MISCELLANEOUS   GARDEN    INSECTS 


427 


of  resin  soap  should  be  added  to  render  it  more  adhesive,  although 
good  results  have  been  secured  without  the  stickcM-.  Such  spraying 
should  be  given  as  soon  as  cutting  is  over  and  should  l)e  repeated 
once  or  twice  at  intervals  of  ten  days.  Where  the  young  shoots 
are  kept  closely  cut  and  the  bed  is  then  sprayed,  there  should  be  no 
trouble  to  control  the  pest,  and  young  beds  should  be  kept  thor- 
oughly sprayed  with  arsenate  of  lead  from  the  time  the  beetles 
appear  until  danger  from  injury  is  over. 


The  Twelve-spotted  Asparagus-beetle  * 

The  Twelve-spotted  Asparagus  Beetle  is  also  of  European 
origin,  having  been  first  introtluced  into  this  country  near 
Baltimore,  Md.,  in  ISSl.  Since  then  it  has  become  almost  as 
widely  distributed  as  the  previous  species. 

The  beetles  may  be  distinguished  from  the  last  species  ])y  the 
broader  wing-covers,  each  of  which  is  orange-red ,  mark':^d  with  six 


'XJ 


Fig.  306. — The  twelve-spotted  asjmragus-beetle  {Crioceris  l2-punctata  Linn.): 
a,  beetle;  b,  larva;  c,  second  abdominal  segment  of  larva;  d,  same  of 
c,  asparagi — a,  b,  enlarged;  c,  d,  more  enlarged.  (After  Chittenden, 
U.  S.  Dept.  Agr.) 

black  spots.  The  chief  injury  by  this  species  is  by  the  beetks 
which  emerge  from  hibernation  feeding  on  the  3'oung  shoots. 
Later  generations  attack  the  foliage,  Ijut  the  larvre  seem  to  prefer 
to  feed  upon  the  I'ipening  l)ei-i-i('s.     Tlic  larva  is  of  tlie  same  gen- 

*  Crioceris  12-pinictata  Linn.     See  F.  JI.  f'hittenden,  I.e. 


428         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

eral  appearance  as  that  of  the  preceding  species,  but  may  be  dis- 
tinguished by  its  orange  color.  The  eggs  are  laid  singly,  and  arc 
attached  on  the  sides  instead  of  on  end.  They  are  deposited 
mostly  on  old  plants  toward  the  ends  of  the  shoots  which  bear 
ripening  berries  lower  down.  Soon  after  a  larva  hatches  it  finds  its 
way  to  a  berry  and  feeds  upon  its  ripening  pulp,  from  which  it 
migrates  to  another,  feeding  upon  several,  perhaps,  before  full 
growth  is  obtained,  when  it  drops  to  the  ground  and  pupates  like 
the  last  species.  The  life  cycle  is  essentially  the  same  and  there 
are  probably  the  same  number  of  generations. 

Control. — The  remedies  advocated  for  the  previous  species 
will  be  found  satisfactory  except  those  which  are  directed  against 
the  larvte,  as  the  hal^it  of  the  larva  of  concealing  itself  in  the  berry 
would  make  the  application  of  insecticides  to  the  seedstalks  of 
little  use. 

The  Asparagus  Miner  * 

Occasionally  injury  by  the  small  white  maggots  of  a  fly  have 
been  observed  in  the  asparagus  beds  of  Long  Island,  California, 
Pennsylvania,  Massachusetts  and  District  of  Columbia,  but  the 
damage  seems  rarely  to  be  very  serious.  The  adult  is  a  small  black 
fly  about  one-sixth  of  an  inch  long  and  is  usually  found  on  the 
flowers  of  the  asparagus,  and  occurs  from  New  England  to  Ten- 
nessee. These  flies  emerge  early  in  June.  The  exact  manner  of 
egg-laying  has  not  been  observed,  but  the  young  maggots  are  found 
mining  just  beneath  the  surface  of  the  stalks,  especially  young 
stalks.  The  maggots  are  about  one-fifth  an  inch  long,  pure 
white,  except  the  black  rasping  hooks  which  project  from  the  head. 
When  full  grown  the  maggots  change  to  puparia  beneath  the  epi- 
dermis. The  next  brood  of  adult  flics  emerge  early  in  August. 
A  second  brood  of  maggots  seems  to  occur  and  the  puparia  of  the 
second  brood  pass  the  winte"!',  and  from  them  come  the  flies  early 
the  next  summer. 

*  Agromyza  simplex  Loew.  Family  Agromyzidoe.  See  Sirrine,  Bulletin 
189,  N.  Y.  Agr.  Exp.  Sta.;  Chittenden,  Bulletin  66,  Part  I,  Bureau  of  Ento- 
mology, ])p.  1  and  .'),  Fig.  2. 


MISCELLANEOUS   GARDEN   INSECTS 


420 


Injui'v  from  tlir  luiniug  of  (lie  luajifiols  has  been  most  serious 
on  seedling  luul  newly  set  beds,  though  it  may  occur  on  cutting 
beds,  being  apparent  by  the  plants  turning  yellow  and  dying  much 
earlier  than  they  naturally  do. 

Pulling  the  old  stalks  and  biu'ning  them  in  late  summer  seems 


Fig.  307. — The  asparagus  miner  (Agromyza  simplex  Loew) :  at  left,  side  view 
of  fly;  a,  larva;  b,  thoracic  spiracles;  c,  anal  spiracles;  d,  puparium  from 
side;  e,  same  from  above;  /,  section  of  asparagus  stalk  showing  injury 
and  location  of  puparia  on  detached  section — a,  e,  much  enlarged;  /, 
slightly  reduced.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

to  be  the  best  means  for  controlling  the  pest  from  our  present 
knowledge  of  it,  which,  however,  is  still  rather  meager.  Dr. 
Chittenden  has  suggested  that  letting  a  few  stalks  grow  as  a  trap- 
crop  to  which  the  flies  might  l^e  lured,  and  then  destroying  these 
stalks,  nught  protect  the  cutting  beds. 


CHAPTER  XXI 
INSECTS  INJURIOUS  TO  THE  SWEET  POTATO  * 

The  Sweet-potato  Flea-beetle  f 

As  soon  as  the  sweet-potato  plants  are  set  out  they  are  often 
attacked  by  hordes  of  hungr}-  little  l)rownish  flea  beetles.  Small 
channels  are  eaten  out  of  l^oth  surfaces  of  the  leaf  in  a  very  char- 
acteristic manner,  quite  different  from  the  work  of  other  flea- 
beetles  (Fig.  309) ,  and  often  the  whole  surface  is  seared  but  never 
punctured.     As  a  result  many  of  the  leaves  of  the  seedling  arc 


Fig.  308. — The  sweet-potato  flea-beetle   {Cfui'locncnia  conjinis    Lee.):    adult 
and  larva — much  enlarged.     (After  J.  B.  Smith.) 

killed  outright,  turn  brown,  and  decay,  while  new  leaves  put 
out  from  below,  thus  checking  the  growth.  These  attacks  have 
been  found  to  be  worst  on  low  land  and  that  previously  in  sweet 
potatoes,  and  are  always  first  noticed  near  fence  rows  or  woodland 
where  the  beetles  have   hibernated.     The   beetle  is  bronzed  or 

*See  Sanderson,  Bulletm  59,  Md.  Agr.  Exp.  Sta.;  J.  B.  Smith,  Bulletin 
229,  N.  J.  Agr.  Exp.  Sta. 

t  Choetocnema  conjinis  Lee.     Family  Ciirysomclidcr.     See  Smith,  1.  c.,  p.  4. 

4:;o 


INSECTS  INJURIOUS  TO  THE  SWEET  POTATO  431 

bi'as.sy-browii,    about    oiie-sixte(nitli  inch  long,    tliick  set,  and  the 
wing-covers  when  seen  under  a  Icnis  are  deeply  striated. 

Life  History. — The  beetles  hibernate  over  winter  in  rubljisli, 
under  logs,  leaves  or  other  vegetation,  and  emerge  early  in  May. 
They  mate  as  soon  as  they  have  fed  a  little,  and  disappear  by  the 
middle  of  June  in  New  Jersey.  But  little  is  known  of  the  early 
stages  of  the  insect  and  the\'  have  never  Ijcen  found  on  sweet- 
potato  plants.  The  larviu  have  been  found,  however,  feeding  on 
the  roots  of  bindweed.  The  larva  (Fig.  SOS)  is  a  slender,  white 
grub,    about   one-eighth    inch    long,   and   feeds   externally   upon 


Fig.  309. — Sweet-potato  leaves  injured  by  the  sweet -potato  flea-beetle.    (After 

J.  B.  Smith.) 

the  smaller  roots.  The  beetles  appear  again  in  August,  but  do 
not  as  a  rule  feed  on  sweet  potatoes,  preferring  bindweeds  and 
wild  morning-glories,  from  which  they,  disappear  in  late  September. 
Control.  By  dipping  the  plants  in  arsenate  of  lead  1  pound  to 
10  gallons  of  water,  as  they  are  being  set,  they  will  be  protected 
and  any  beetles  feeding  on  them  will  be  killed.  The  plants  should 
be  allowed  to  dry  slightly  before  being  set.  Dipping  the  plants 
is  much  better  than  spraying  them  later,  as  it  is  practically 
impossible  to  completely  cover  the  plant  by  spraying,  as  may  be 
done  in  dipping,  which  is  much  quicker  and  less  expensive.    Late- 


432         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

planted  sweet  potatoes  are  much  less  serioush'  injured,  as  the 
beetles  will  seek  out  their  wild  food-plants  and  l^ecome  established 
upon  them,  so  that  late  planting  may  be  resorted  to  when  neces- 
sary or  more  convenient.  Well  grown,  stocky  plants  will  better 
withstand  injury,  and  liberal  fertilization  will  enable  them  to  make 
a  quick  growth  even  if  slightly  checked. 

Tortoise-beetles  or  Gold-bugs  * 

Of  all  the  insects  affecting  the  s\\('et  jxjtato,  the  l)rilliant,  little 
golden  beetles  which  form  one  tribe  {CassUlw)  of  the  large  family 
of  leaf-beetles,  are  the  most  common  and  are  quite  peculiar  to  it. 
They  are  beautiful  insects,  some  of  the  species  appearing  like  drops 
of  molten  gold,  which  has  given  them  the  name  of  "  gold-bugs," 
while  the  broad  expansion  of  the  thorax  and  wing-covers  gives 
them  a  fancied  resemblance  to  a  tortoise;  hence  the  name  "  tortoise- 
beetles."  The  species  affecting  the  sweet  potato  are  classed  in 
three  different  genera,  but  are  sufficiently  alike  in  their  general 
habits  and  life  history  to  be  treated  together.  -j 

Life  History. — The  beetles  hibernate  over  winter  and  in  tile 
spring  before  the  sweet-potato  plants  are  set  they  feed  on  their 
native  food-plant,  the  morning  glory.  As  soon  as  the  plants  are 
set  out,  the  beetles  commence  to  eat  large  round  holes  in  the  leaves, 
and  so  riddle  them  that  many  must  often  be  replanted.  The  worst 
damage,  however,  is  done  to  the  set  on  which  the  eggs  are  laid. 
Rarely  are  the  new  shoots  seriously  eaten  or  are  eggs  laid  upon 
them.  The  larvae  hatch  during  the  first  half  of  June  in  Maryland, 
and  require  slightly  over  two  weeks  to  become  full  grown.  Though 
the  larvffi  do  considerable  damage  by  eating  the  foliage,  it  is  not 
nearly  as  serious  as  that  done  by  the  beetles.  The  larvae  are  almost 
as  disagreeable  as  the  adult  l^eetles  are  attractive,  but  are  never- 
theless very  interesting  creatures.  Each  of  them  is  provided  with 
a  tail-like  fork  at  the  end  of  the  body  which  is  almost  as  long  as 
the  body,  and  in  those  species  in  which  it  is  depressed,  entirely 

*  Family  Chrysomelidce. 


IN8EC/I\S   INJURIOUS  TO   THE  SWEET   POTATO 


433 


conceals  the  insect.  Upon  (his  fork  is  heaped  the  excrement  and 
cast  skins  of  the  hirva,  and  vv  en  covered  by  this  "  umbrella  "  it  is 
with  great  difficulty  that  the  larva  is  distinguished  from  a  bit  of 
mud  or  a  bird-dropping.  The  manner  in  which  this  fork  increases 
with  the  size  of  the  larva  is  rather  interesting.  At  each  molt,  the 
fa3ci-fork  of  the  last  stage  is  held  upon  the  new  fseci-fork,  and  in 
this  way  those  of  the  difTerent  stages  are  telescoped,  the  one  inside 
the  other,  and  the  stage  of  growth  of  the  larva  may  be  readily 
determined  by  the  number  of  cast  skins  held  on  the  fork.  From 
tlie  likeness  of  this  burden  to  a  jDack,  the  larvte  are  often  known 
as  '^  i^eddlers."  In  order  to  more  firndy  bind  the  excrement  and 
cast  skins  to  the  fork,  the  larva?  fasten  them  together  by  a  fine 
network  of  silken  threads,  which  are  attached  to  the  spines  at  the 
sides  of  the  body.  When  fully  grown  the  larva  fastens  itself  to  a 
leaf,  its  skin  splits  open  along  the  back,  and  from  it  comes  the 
pupa,  which  is  held  to  the  leaf  by  its  caudal  fork,  which  is  securely 
encased  in  the  faci-fork  of  the  larval  skin.  About  a  week  later 
the  adult  l^eetle  emerges,  eats  for  a  few  days  and  then  disappears 
from  the  sweet-potato  patch  until  the  following  spring,  doubtless 
feeding  on  morning  glory  until  it  enters  hibernation. 

The  Two-Striped  Sweet-potato  Beetle  * 

This  is  usually  the  most  common  of  the  tortoise  beetles  attack- 
ing   sweet  potatoes.      Tlie    beetle    is    pale    or    brownish-yellow, 


Fig.  310. — ^The  two-striped   sweet-potato  beetle  (Cassida  hiviltata  Say):    1, 
larvsc  on  leaf;  2,  larva;  3,  pupa;  4,  beetle — all  enlarged.     (After  Riley.) 


striped  with  black  as  shown  in  Fig.  310,  and  the  larva  is  yellowish- 
white,  with  a  longitudinal  band  along  the  back,  on  either  side  of 
*  Cassida  bivittata  Say.     Family  Chrysomelidoe. 


434      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

which  is  a  much  Hghter  band.  This  species  differs  from  the  others 
in  that  the  hirva  does  not  use  its  fajci-fork  for  carrying  excrement, 
but  merely  covers  it  with  cast  skins  and  holds  it  at  an  angle  from 
the  body,  instead  of  close  over  the  back. 


The  Black-legged  Tortoise-beetle  * 

This  species  very  closely  resembles  the  following  one,  the  gol- 
den tortoise-beetle,  but  it  is  not  so  brilliant,  is  larger,  has  black 
legs,  and  the  three  black  spots  on  each  wing-cover  are  larger  and 
more  conspicuous.  The  larva  is  a  bright  straw-yellow,  with  two 
crescent-shaped  black  marks  just  back  of  the  head  and  with  the 
spines  at  the  side  of  the  body  tipped  with  black.  It  is  considerably 
larger  than  the  larvaB  of  the   other  species  and  may  be  easily 


Fro.  .311. — The  black-legged  tortoise-beetle.     (Cassida  nigripes  Oliv.):   n,  h, 
lavviv;  c,  pupa;  (^/,  beetle.     (After  Riley.)     Egg.s  at  left — all  enlarged. 

recognized  by  the  characteristic  way  in  which  the  dung  is  spread 
on  the  fieci-fork  (Fig.  311,  a).  The  larva;  of  this  species  also  do 
more  injury  than  the  others,  though  possibly  not  as  common. 
The  eggs  of  the  other  species  are  laid  singly,  so  that  onl}^  one  or 
two  larvte  will  be  found  on  a  plant,  or  if  more  occur  they  are  scat- 
tered, but  the  eggs  of  this  species  are  laid  in  rows  of  from  three  to 
a  dozen,  and  upon  hatching  the  larvae  feed  together,  thus  making 
the  injury  more  noticeable. 

*  Cassida  nigripes  Oliv.     Family  Chrysomelidoe. 


INSECTS   INJURIOUS    TO    THE  SWEET   POTATO 


435 


The  Golden  Tortoise-beetle  * 

This  is  a  very  comnion  species  and  may  Ix'  found  on  morning- 
glory  vines  throughout  the  summer.  The  beetles  upon  first 
emerging  are  a  dull  orange  color  Nvith  three  prominent  black  dots 
on  each  wing-cover,  but  a  little  later  they  change  to  a  metallic  gold, 
shining  like  the  most  brilliant  tinsel,  and  the  black  spots  are  less 
noticeable.  All  of  the  tortoise-beetles,  and  this  species  in  particu- 
lar, have  the  habit  of  dropping  quckly  to  the  ground  and  feigning 
death  when  disturljcd.  The  eggs  are  quite  different  from  those  of 
other  species,  having  three  spiny  prongs  projecting  from  the  pos- 


lM(i.  312. — The  golden  tortoise-beetle  {Coptocycla  bicolnr  Fab.):    a,  h,  larvae; 
c,  pupa;  (/,  beetle;  egg  at  right — .all  enl.arged.      (After  Riley). 

terior  margin  (Fig.  312) .  The  larva  is  easily  distinguished  b}'  being 
nearly  concealed  by  the  heavy  load  of  excrement  which  is  tri-lob^d 
in  outline.  Though  usually  of  a  dark-brown  color  with  a  paler 
shade  along  the  middle  of  the  back,  when  the  faeci-fork  is  raised 
the  light  color  extends  over  the  entire  upper  side.  The  pupa,  with 
the  loaded  fork  still  held  close  to  the  back,  is  hardly  distinguishable 
from  the  larva  at  first  glance,  but  if  the  fork  is  removed  it  may  be 
distinguished  from  nearly  releated  pupae  by  the  three  dark  stripes 
on  the  prothorax  and  similar  m-arkings  over  the  abdomen. 


*  Coptocycla  bicolor  Fab.     Family  Chrysomelidoe. 


436         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Mottled  Tortoise-beetle  * 

This  beetle  is  strikingly  different  from  the  other  species  in 
being  black,  marked  with  six  irregular  golden  spots,  and  with  a 
band  of  black  extending  across  the  shoulders  to  the  edge  of  the 
transparent  margin  of  the  wing-covers.  The  larva  is  a  pale 
straw-yellow  color  during  the  first  four  stages  when  it  carries 
excrement  on  the  fseci-fork  in  a  peculiar  branched  shape  much 
like  that  of  the  black-legged  tortoise-beetle  larva,  but  after  the 
last  moult  the  color  changes  to  a  pea  green,  and  all  the  excrement 
is  removed  from  the  fseci-fork,  which  makes  the  larva  very 
difficult  to  recognize  on  a  green  leaf.  Inasmuch  as  the  larva 
does  not  feed  and  remains  entirely  motionless  during  this  last 
stage,  this  change  of  color  is  very  evidently  of  protective  value. 
The  pupa  is  also  a  bright  green,  marked  only  by  a  black  ring 
aroifnd  each  of  the  first  pair  of  abdominal  spiracles. 

The  Argus  Tortoise-beetle  t 

This  is  the  largest  of  the  tortoise-beetles  found  on  sweet 
potato,  though  not  as  common  as  the  preceding,  and  is  also 
injurious    to  raspberry  and    horseradish,  and  it  feeds   on  milk- 


FiG.  313. — Thf  argus  tortoise-beetle  {Chehjmorpha  argus  Licht.):    a,  beetle; 
b,  eggs;   c,  larva — all  enlarged. 

weeds  and  species  of  Convolvulus.  The  beetles  are  usually  a  brick- 
red  color,  with  six  black  dots  on  the  prothorax  and  six  on  each 
wing-cover,  but  they  are  exceedingly  variable  in  size  and  color, 

*  Coplocycla  signifera  Herbst.     Family  ChrysomeUdoe. 
f  Chelymorpha  argus  Licht.     Family  Chrysomelidoe. 


INSECTS  INJURIOUS  TO  THE   SWEET  POTATO         437 

even  from  the  same  lot  of  eggs.  The  expansion  of  the  margins 
of  the  wing-covers  and  prothorax  found  in  the  other  tortoise- 
beetles  is  almost  lacking.  The  eggs  are  laid  in  a  bunch,  each 
supported  by  a  long  stalk  or  pedicle.  When  the  larvae  hatch 
they  huddle  together  on  the  leaves  and  very  rapidly  defoliate  a 
plant.  When  full  grown  a  larva  is  about  one-half  inch  long  with 
the  fseci-fork  half  as  long  again,  slightly  convex  above,  of  a  dirty 
yellowish  color  marked  with  numerous  dark-l^rown  tuljercles 
and  prominent  lateral  spines  as  shown  in  Fig.  313.  The  larva 
usually  stands  with  the  caudal  segments  elevated  and  the  fa'ci- 
fork  slanting  backward.  The  pupa  is  of  a  yellowish  color, 
marked  with  dark  brown,  which  becomes  almost  black.  The 
ground  color  of  the  pupa  is  almost  concealed  by  a  bluish  bloom 
or  waxy  excretion  resembling  mold. 

Control. — From  the  similarity  of  their  life  history  and  habits 
all  of  these  species  may  be  treated  at  once.  As  the  beetles  do  the 
most  injury  just  after  the  plants  are  set,  they  should  be  dipped 
in  arsenate  of  lead  when  setting,  as  advised  for  the  flea-beetle. 
If  this  has  not  been  done  or  if  the  beetles  are  injurious  in  the 
forcing  lied,  the  plants  should  be  thoroughly  sprayed  with 
arsenate  of  lead,  3  pounds  per  barrel,  or  Paris  green,  ^  pound  per 
barrel  with  h  pound  of  freshly  slaked  lime. 

Saw-flies  * 

In  1SS6,  Dr.  C.  V.  Riley  described  the  injury  and  various 
stages  of  a  saw-fly, f  the  larvse  of  which  had  practically  ruined  a 
crop  of  sweet  potatoes  at  Ocean  Springs,  Miss.  The  pest  was 
somewhat  injurious  for  the  next  two  years,  but  since  then  has 
not  been  specially  injurious,  though  adult  flies  have  been  noticed 
on  sweet-potato  and  morning-glory  vines  in  Nebraska.  Doubt- 
less its  control  is  due  to  the  effective  work  of  parasites  which 
were  reared  by  Dr.  Riley  from  the  larvse,  and  which  probably 
prevent  the  undue  increase  of  the  species. 

*  Family  Tenthredinidoe. 
t  'Schisocerus  ebenm  Norton. 


438^       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  larvae  of  another  insect  of  the  same  genus  *  was  reported 
as  seriously  injuring  the  crop  in  Accomac  County,  Virginia,  in 
1891.  Concerning  this  injury  the  grower,  C.  W.  Stockley,  wrote, 
"  Last  year  (1890)  was  the  first  time  they  made  their  appearance 
in  my  potato  patch.  They  came  the  first  of  July  and  deposited 
their  eggs  on  the  leaves;  when  the  eggs  hatched  these  worms 
would  eat  the  leaves  to  a  comb.  This  continued  for  about  four 
weeks.  The  potatoes  where  the  fly  was  did  not  make  any  yield 
at  all.  This  year  the  fly  made  its  appearance  the  same  time  as 
it  did  last  year."  Since  then  no  injur}^  has  l)oen  reported  by 
this  species,  though  the  adults  are  occasionally  seen. 

Control. — An  arsenical  spray  as  advised  for  the  tortoise-beetles 
wull  Ije  found  effective  for  destroying  the  saw-fly  larva;  and 
should  be  applied  as  soon  as  the  injury  is  noticed,  or  preferably 
just  as  the  eggs  are  hatching. 

The  Sweet-potato  Root-borer  f 

Since  1890  sweet  potatoes  have  been  seriously  injured  in  parts 
of  Texas  and  Louisiana  by  a  small  white  grulj  which  Isores  into  the 
stems  and  tubers  both  in  the  field  and  in  storage,  but  strangely 
it  has  not  spread  elsewhere  in  this  country.  In  Texas  the  worst 
injuiy  has  been  in  Calhoun  and  neighboring  counties  along  the 
Gulf  Coast  where  extensive  growing  of  sweet  potatoes  has  been 
abandoned  on  account  of  the  pest.  During  recent  years  it  has 
spread  to  central  Texas  and  there  seems  to  be  no  reason  why  it 
should  not  spread  over  the  Gulf  States.  It  is  a  cosmopolitan 
insect  being  reported  from  China,  India,  Madagascar,  Australia 
and  Cuba.  It  was  first  noticed  in  the  vicinity  of  New  Orleans 
in  1875  and  has  since  spread  northward  along  the  Mississippi.! 
In  1879  it  was  reported  from  Florida  and  was  studied  1)}'  Professor 
J.  H.  Comstock.§ 

The  adult  beetle  is  a  rather  slender  insect,  about  one-quartei 

*  Schizocerus  privatus  Norton. 

t  Cylas  formicurius  Oliv.     Family  Curculionidoe. 

t  Bulletin  28,  La.  Agr.  Exp.  Sta.,  p.  999. 

S  See  Report  U.  S.  Comm.  Agr.,  for  1879,  p.  249. 


INSECTS  INJURIOUS    TO   THE  SWEET  POTATO 


439 


inch  long,  of  a  bluish-black  color,  with  a  reildish-bruwn  prothorax, 
and  has  received  its  specific  name,  forniicariua,  from  its  fancied 
resemblance  to  an  ant. 

Life  History. — The  yellowish-white,  oval  eggs  are  deposited 
in  small  cavities  eaten  out  by  the  mother  beetle  either  at  the 
base  of  the  vine  or  at  the  stem  end  of  the  tuberous  root,  or  in 
the  tubers  in  storage.  The  small  grubs  commence  to  burrow 
in  the  vine,  sometimes  maturing  in  the  vine  l^efore  any  tubers 
have  developed,  but  usually  they  descend  to  the  tubers,  w^hich 


Fig.  314. — The  sweet-potato  root-borer  (Cylas  formicarius) :  extreme  left 
hand  figure,  adult  beetle,  with  enlarged  antennae  at  right;  figure  at 
left  center,  pupa;  at  right  center,  larva;  at  extreme  right,  portion  of 
sweet-potato  tuber  channeled  by  borer — all  figures  except  the  last  con- 
siderably enlarged;  natui-al  sizes  indicated  by  hair  lines.  (After  Far- 
mer's Bulletin,  No.  26,  U.  S.  Dept.  Agr.) 

in  the  course  of  the  season,  and  with  the  aid  of  the  beetles,  they 
thoroughly  riddle.  The  full-grown  larva  is  aljout  one-quarter 
inch  long,  whitish  with  light  brown  head,  the  segments  are  strongly 
constricted,  and  the  legs  are  wanting,  l^eing  represented  by  mere 
tubercles.  The  grub  forms  a  small  cavity  at  the  end  of  the 
l)urrow  and  transforms  to  the  pupa.  In  this  stage  it  remains  from 
one  to  two  weeks,  when  the  adult  beetle  emerges  and  after  a  few 
days  commences  to  lay  eggs  for  another  generation.     The  whole 


440        INSECT  PESTS  OF   FARM,   GARDEN  AND  ORCHARD 

life  cycle  requires  from  thirty  to  forty  chiys,  .so  that  there  iiiay 
be  several  generations  in  a  year,  Professor  Comstock  having 
observed  three  generations.  In  central  Texas  the  beetles  hiber- 
nate over  winter,  but  in  south  Texas  they  continue  to  breed  in 
the  bins  during  the  winter. 

Control. — The  following  measures  of  control  are  recommended 
by  Professor  A.  F.  Conradi,  who  has  studied  the  species  in  Texas.* 

"  When  the  insect  is  known  to  be  present,  tubers  should  not 
be  allowed  to  remain  exposed,  and  should  he  covered  with  soil. 
Where  beetle  attack  is  anticipated,  deep  planting  should  bo 
practiced,  and  if  conditions  will  permit  the  planting  should  be  in 
flats,  because  outbreaks  will  be  more  readily  noticed  than  when 
planted  in  ridges.  Such  planting  will  permit  of  cultivation  that 
will  keep  the  cracks  in  the  soil  closed  during  drought,  thus  shut- 
ting up  all  entering  channels  by  which  the  adults  may  reach  the 
tubers.  When  the  crop  is  known  to  be  infested,  it  should  be 
harvested  as  soon  as  possible,  for  every  day  the  infestation  will 
increase  and  the  value  of  the  crop  will  decrease.  All  tubers 
showing  no  sign  of  infestation  should  be  separated  from  the 
infested  ones.  The  former  should  be  placed  in  a  weevil-tight 
bin  [and  fumigated  with  carl)on  bisulfide  if  not  sold  immediately — 
E.  D.  S.],  and  the  latter  destroyed  absolutely.  The  vines  should 
1)0  gathered  and  burned,  and  the  grower  should  convince  him- 
self .  .  .  that  no  vines  or  tubers  remain  in  the  field."  The  pest 
may  be  disseminated  in  sweet-potato  sets  intended  for  planting, 
and  may  be  spread  great  distances  by  the  tubers  on  the  open 
market,  so  that  seed  potatoes  or  slips  should  be  secured  from 
localities  known  to  be  free  from  it  or  should  be  thoroughly  fumi- 
gated. The  weevils  often  gnaw  the  plants,  and  Professor  Conradi 
advises  thorough  spraying  with  Paris  green  or  arsenate  of  lead 
while  they  are  feeding.  Potatoes  in  bins  should  be  thoroughly 
fumigated  with  carbon  bisulfide,  5  pounds  to  100  bushels  for 
thirty  hours  (see  page  57). 

*  See  Bulletin  89,  Texas  Agr.  Exp.  Hta.,  p.  40. 


CHAPTER  XXII 


INSECT8  IxNJURIOUS  TO  THE  STRAWBERRY  * 


The  Strawberry  Root-louse  f 

If  bare  spots  arc  found  in  llic  strawljcrry  IxmI  and  llic  ncigldjor- 
ing  plants  are  unhealthy,  the  presence  of  tlu>  root-lous(;  may  be 
suspected,  especially  if  ants  arc  abundant  around  tli(^  plants. 
If  present,  the  small  dark  green  or  blackish  aphides  will  be  found 
clustered  on  the  roots  and  stems,  caus- 
ing the  plants  to  wither  and  die.  The 
individual  aphid  is  only  about  one- 
twentieth  inch  long,  and  deep  bluish 
or  greenish-black  when  mature,  the 
younger  stages  being  lighter,  and 
somewhat  pear-shaped  as  shown  in 
Fig.  315. 

Injury  by  this  pest  was  first  noted 
in  southern  Illinois  in  1884  and  a  few 
years  later  it  became  troublesome  in 
Ohio.  In  the  late  '90s  it  ruined 
many  beds  on  the  Maryland-Delaware 
peninsula  and  became  established  in 
New  Jersey.  Since  then  it  has  become  distril^utcd  on  plants 
throughout  most  of  the  States  east  of  the  Rockies,  injury  having 
been  noted  in  New  Hampshire,  Michigan,  Minnesota,  Kansas, 
Texas,    and    Kentucky.     Injury   is  most  severe    on   light  sandy 

*  See  L.  Bruner,  Report  Nebraska  Horticultural  Society,  pp.  49-100; 
J.  B.  Smith,  Bulletin  225,  N.  J.  Agr.  Exp.  Sta.;  A.  L.  Quaintance,  Bulletin 
42,  Fla.  Agr.  Exp.  Sta.;  S.  A.  Forbes,  13th  Report  State  Ent.  of  111.,  pp. 
60-180. 

t  Aphis  forbesi  Weed.  Family  Aphidida;.  See  Sanderson,  Bulletin  40^ 
12th,  13th  and  14th  Reports,  Del.  Agr,  Exp.  Sta. 

441 


Fig.  315.  —  The  strawberry 
root -louse  (Aphis  forbesi 
Weed) :  vingless  viviparous 
female  of  late  summer — 
greatly  enlarged. 


442      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

soils  and  the  pest  rarely  becomes  very  troublesome  on  heavier 
soils.  Injury  is  also  more  or  less  periodic,  the  aphides  almost 
disappearing  after  doing  serious  injury  for  two  or  three  years. 
Fortunately  the  strawberry  is  the  only  food  plant  and  the  root- 
lice  found  on  other  crops  are  entirely  different  species. 

Life  History. — During   the   winter   the   small,    shining   black 
eggs  may  be  found  thickly  clustered  upon  the  stems  and  along 


Pig.  316. — Strawberry  root-lice  clustered  on  small  rootlets  from  crown  of 
plant — greatly  enlarged. 

the  midribs  of  the  green  leaves.  They  are  mere  specks,  one- 
thirty-fifth  inch  long  and  oval  in  shape.  In  earh-  winter  as  many 
as  sixty-five  have  been  found  on  one  leaf,  but  many  fall  off  and 
are  destroyed  before  spring.  The  eggs  hatch  early  in  April  in 
Delaware,  the  exact  time  depending  on  the  season.  The  young 
aphides  feed  a  little  on  the  leav(\s  ])(>aring  the  eggs  but  soon  find 
their   way   to   the   tender   }'Oung   leaves   of  the    crown.     These 


INSECTS  INJURIOUS  TO   THE  STRAWBERRY  443 

aphides  of  the  first  generation  become  full  grown  in  twelve  to 
fifteen  days.  The  adults  soon  commence  to  give  birth  to  young 
aphides,  bearing  fifteen  or  twenty  within  a  few  days.  All  of  the 
aphides  of  this  generation  are  females,  as  are  all  those  of  the 
summer  generations,  the  males  appearing  only  in  the  fall.  The 
young  of  the  second  generation  mature  and  reproduce  in  the  same 
manner  and  in  about  the  same  time  as  the  first  generation.  Until 
the  last  of  April  but  few  ants  are  seen,  but  about  that  time  they 


Fig.  317. — Eggs  of  strawberry  root-louse  on  leaf  stem. 

become  active  and  carry  the  young  aphides  from  the  leaves 
down  to  the  roots,  where  a  colony  of  a  dozen  or  more  is  established 
on  each  plant.  Xo  aphides  are  found  on  the  roots  until  the  ants 
appear,  and  they  are  entirely  responsible  for  the  aphides  infesting 
the  roots.  The  ants  continue  to  care  for  the  aphides  during  the 
summer,  carrying  them  to  new  plants  when  they  become  over- 
crowded or  the  plant  dies,  and  so  are  responsible  for  the  spread 
of  the  pest.  The  first  generations  are  entirely  wingless,  hxii  wluni 
the  third  generation  matures  a  large  mnubei-  are  winged.      These 


444        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

winged  females  are  common  in  late  May  and  early  June.  Their 
bodies  are  somewhat  smaller  than  those  of  the  wingless  forms, 
and  appear  to  be  shiny  black,  though  really  a  deep  green.  The 
wings  expand  about  one-sixth  inch,  slightly  over  three  times  the 
length  of  the  body.  They  are  also  carried  to  the  roots  by  the 
ants,  wherever  they  are  found,  and  most  of  them  deposit  their 
young  on  the  roots.  Although  these  winged  females  aid  in  spread- 
ing the  pest  in  a  bed,  they  probably  do  not  migrate  far  unless 


Fig.  318. — Strawberry  root-lice  which  have  been  killed  by  parasites,  with 
one  of  the  little  parasitic  flies  which  has  just  emerged. 

carried  by  the  wind  from  a  l^aclly  infested  bed  where  they  have 
become  overcrowded.  Reproduction  continues,  one  generation 
following  another  about  every  two  weeks,  during  the  summer  and 
early  fall.  Part  of  the  fourth  generation  is  winged,  but  the  remain- 
ing generations  are  wingless.  In  Delaware  the  viviparous  females 
are  common  on  the  roots  until  cold  weather,  but  doubtless  further 
south  they  may  continue  to  I'eproduce  during  the  winter.  Late 
in   October  and  early  in   November  the   offspring  develop  into 


INSECTS   INJURIOUS   TO  THE   STRAWBERRY  445 

true  males  and  females  which  j)air  and  i-eprochicc  by  eggs.  The 
egg-laying  females  are  very  similar  to  the  summer  generations 
in  general  appearance,  though  of  a  green  color,  with  often  a 
yellowish  or  reddish  shade  on  the  middle  of  the  alxlomcni.  The 
males  are  much  smaller  and  are  hardly  to  be  distinguished  from 
the  third  stage  of  the  female  nymphs,  and  are  greatly  outnum- 
bered by  the  females.  Each  female  deposits  about  four  eggs, 
which  are  at  first  a  bright  orange  color,  Ijut  turn  black  in  a 
day  or  two. 

Were  it  not  for  its  parasitic  enemies  this  insect  would  alwaj^s 
be  a  most  formidaljle  strawberry  pest,  l)ut  fortunately  they  are 
very  efficient  in  its  control  whenever  it  becomes  aljundant.  The 
adult  parasites  are  little  wasp-like  flies,*  nearly  related  to  those 
which  parasitize  the  melon-aphis  and  green-bug.  They  deposit 
their  eggs  in  the  plant-lice,  and  the  maggots  live  within  the 
aphides,  usually  but  one  in  each.  The  aphid  soon  dies  from  the 
effects  of  the  parasitism,  the  skin  becoming  dry  and  inflated, 
from  which  shell  the  adult  parasite  emerges  through  a  circular 
hole  as  shown  in  Fig.  318.  Such  parasitized  aphides  are  easily 
recognized  and  should  never  be  destroyed. 

Control. — To  prevent  injury  care  must  be  taken  to  secure 
uninfested  plants  and  to  plant  them  on  land  not  already  infested. 
Do  not  replant  berries  on  infested  land  until  it  has  been  in  some 
other  crop  for  a  year  or  two.  As  the  aphides  and  their  eggs  arc 
i-eadily  transported  on  plants,  it  is  important  that  they  be  secured 
from  sources  known  to  be  free  from  tlu;  pest.  If  there  is  an\- 
doubt  about  this  or  if  they  are  known  to  be  infested,  the  plants 
should  be  disinfected  before  setting.  This  can  be  done  only 
after  all  the  eggs  have  hatched,  as  there  is  no  treatment  that  will 
kill  the  eggs  without  injuring  the  plants.  Setting  must  be  delayed, 
therefore,  until  all  eggs  have  hatched.  The  most  practicable 
method  for  disinfecting  plants  is  to  dip  them  for  a  few  minutes  in 
tobacco  decoction  or  dilute  tobacco  extract.  Other  dips  will 
kill  the  aphides,  but  sometimes  injure  the  plants,  while  tobacco 
water  has  been  found  efficient  and  safe.     Plants  may  be  fumigated 

*  Lynphlebus  testaceipes  Cress.,  and  Lygocerus  stigmatus  Say. 


446        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

with  hyrdocyanic  acid  gas  by  the  nurserynian  or  hirgc  grower 
(see  the  author's  Dehiware  l:)ulletin).  If  a  new  l)ed  be  planted 
near  an  old  one  it  may  become  infested  when  the  winged  aphides 
appear  in  early  summer  and  to  prevent  their  migration  it  ma}' 
be  advisable  to  plow  up  the  old  bed  some  time  before  the  winged 
aphides  appear,  or  preferably  the  previous  fall.     One  of  the  best 


Fig.  319. — ^A  Delaware  strawberry  bed  in  summer  of  1900  showing  injury  by 
the  strawberry  root-louse. 


means  of  reducing  the  number  of  aphides  in  a  l)ed  is  to  burn  it 
over  with  a  quick  hot  fire  in  early  spring,  Straw  or  grass  should 
be  scattered  over  the  ])ed  and  burned  just  as  the  growth  of  the 
plants  is  commencing.  As  all  the  eggs  and  young  aphides  are  on 
the  leaves  and  stems,  this  will  practically  clear  the  bed  of  the 
pest,  as  well  as  many  other  insects  and  diseases,  and  if  properly 
done  will  result  in  no  injury.  This  has  been  found  satisfactory 
in  Delaware,  but  if  farther  south,  the  aphides  winter  on  the  roots, 
it  would  not  be  as  effective. 


INSECTS  IXJURIOirS  TO   THE   STRAWBERRY 


447 


The  Strawberry  Crown-borer  * 

Strawberry  plants  are  often  thvarfed  or  killed  by  a  small  white 
larva  which  mines  out  the  interior  of  the  crown,  hollowing  it  out 
from  the  bases  of  the  leaves  to  the  larger  roots.  Usually  l)ut 
one  grub  is  found  in  a  plant,  and  it  looks  very  much  like  a  small 
white  grub  as  it  lies  curled  in  its  l^urrow.  It  is  only  about  one- 
quarter  inch  long,  and  legless,  the  body  being  white  and  the  head 
yellowish  brown.  The  adult  beetle  is  a  small  snout-beetle  about 
one-fifth  inch  long,  of  a  dark  color,  with  head  and  thorax  nearly 
black,  and  on  each  wing-co\Tr  arc  three  black  spots,  the  middle 
one  being  the  largest  and  separated  from  the  others  by  pale  lines. 
According  to  Professor  Garman  the  wings  are  too  small  to  be  used 


Fig.  320. — The  strawberry  ero-mi-borer  {T yloderma  fragrarice  Riley) :  a,  larva. 
h,  c,  beetle — enlarged.     (After  Riley.) 

for  flight  and  this  doubtless  accounts  for  the  slow  spread  of 
the  pest.  Injury  has  been  reported  from  Illinois,  Kentucky, 
Missouri,  and  Nebraska,  but  as  the  larva?  might  be  readily  shipped 
in  plants,  it  is  quite  probable  that  it  has  become  generally 
distributed  but  has  not  done  sufficient  injury  to  attract  attention. 
Life  History. — The  beetles  appear  during  the  latter  part  of 
summer  and  fall  and  hibernate  over  winter  in  the  soil,  emerging 
early  the  next  spring.  The  eggs  have  not  been  observed,  but  are 
undoubtedly  laid  on  the  crown  between  the  bases  of  the  leaves 
in  late  spring.  The  larv?e  develop  in  the  crow^ns  and  become  full 
grown  by  midsummer  or  August  when  they  pupate  in  the  cavities 

*  Tyloderma  fragrarice  Riley.  Family  Curculionidoe.  See  S.  A.  Forbes, 
12th  Report  111.  State  Ent.,  p.  64;  13th  Report,  p.  142;  H.  Garman,  Bulletin 
80,  Ky.  Agr.  Exp.  Sta.,  p.  261. 


nS^Me-TC 


A^ 


448        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

formed  and  the  adult  beetles  emerge  in  late  summer  and  fall. 
There  seems  to  be  but  one  generation  a  year.  Old  plants  are 
worst  injured,  and  runners  formed  late  in  the  season  are  usually 
free  from  the  pest,  as  eggs  are  probably  not  laid  after  June. 

Control. — Frequent  rotation,  plowing  up  the  l)ed  after  one 
or  two  crops,  will  largely  prevent  the  pest  becoming  established. 
Where  the  insect  is  well  established  in  old  beds,  it  will  be  well 
to  secure  plants  from  beds  known  to  l^e  free  from  the 
pest  and  to  plant  new  l)eds  at  some  distance  from  the  old  ones. 
Infestetl  beds  should  have  the  plants  plowed  out  and  raked  up 
and  Inirned  as  soon  as  possiljle  after  the  fruit  is  harvested  and 
before  August.  Owing  to  the  fortunate  fact  that  the  beetle 
cannot  fly  from  field  to  field,  if  the  above  measures  are  consistently 
carried  out  there  should  be  no  trouble  in  controlling  the  injuiy. 

Strawberry  Rootworms  * 

The  larv»  of  three  species  of  common  leaf-beetles  often  feed 
upon  the  roots  of  the  strawberry  and  are  easily  mistaken  for  the 
crown-borer  or  for  small  white  grubs.  They  may  be  distinguished 
from  the  former  by  having  three  pairs  of  small  thoracic  legs  just 
back  of  the  head,  and  from  the  latter  by  their  being  much  thicker. 
These  rootworms  are  from  one-eighth  to  one-sixth  inch  long, 
whitish,  with  brownish  heads,  and  usually  feed  on  the  roots 
externally,  though  sometimes  boring  into  them  or  the  crown. 
Dr.  Forbes  *  has  indicated  the  structural  differences  by  which 
they  may  be  separated  and  shows  that  their  life  histories  are  quite 
dissimilar.  "  The  larva  of  Colaspis  appears  early  in  the  season, 
and  does  its  mischief  chiefly  in  the  months  of  April  and  May, 
the  beetles  beginning  to  emerge  in  June.  That  the  eggs  are  laid 
in  the  preceding  year  is  highly  probable,  in  which  case  the  species 
hibernates  in  the  egg.  Typophoriis,  on  the  other  hand,  certainly 
passes  the  winter  as  an  adult,  doubtless  laying  its  eggs  in  spring, 
and  making  its  principal  attacks  upon  the  plants  in  June  and 

*  Typophorus  canellas  Fab.,  Colaspis  hrunnea  Fab.,  Graphops  pubescem 
Mels.    Family  Chrysomelidce.     See  Forbes,  1.  c-,  p.  150. 


INSECTS  INJURIOUS  TO  THE  STRAWBERRY 


449 


July,  the  l>c('tl('s  ciucru- 
ing  in  the  latter  part  of 
July  and  early  in  August. 
Graphops  hibernates  in 
the  larval  condition,  pu- 
pates in  the  spring,  and 
emerges  in  May  and  June. 
The  eggs  are  prol^ably 
laid  in  July,  and  the 
larvai  make  their  attack 
upon  the  plant  in  August 
and  September.  .  ." — 
Forbes.  Thus  the  larva^ 
of  the  three  species  may 
be  found  throughout  the 
season  where  all  occur. 
The  beetles  are  about 
one-eighth  inch  long  and 
may  be  distinguished  as 
follows  ,  according  t  o 
Bruner:  "  Colaspis  bi-un- 
nea  is  usually  of  a  yel- 
lowish clay  color,  Init 
I'anges  to  y(>llowish- 
brown.  The  Ijoth'  is 
smooth  but  not  shining. 
Typophorus  canellus  is 
usually  shiny ,  black 
above,  varying  to  brown, 
with  fovu"  black  blotches 
on  the  wing-covers.  The 
legs  and  antenna)  are 
always  pale.  Graphops 
puhescens  is  either  green 
or  purple  with  a  bronze 
metallic  sheen,  and  has 


Fig.  32U — The  strawberry  root-borsr  (Typo- 
phorus canellus  Fab.):  a<lult  and  larva — 
very  greatly  enlarged,  hair  hne  at  right  of 
beetle  shows  natural  size.     (After  Pettit.) 


450         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  entire  botly  nioie  or  less  covered  with  a  gray  i)ubescence." 
The  pupic  are  all  found  in  earthen  cells  among  the  roots  of  the 
plants.  The  beetles  of  all  three  species  feed  on  the  foliage  and 
when  numerous  will  attract  attention. 

Control. — Whenever  the  plants  are  not  in  fruit,  the  beetles 
may  be  destroyed  by  spra3'ing  with  \  pound  of  Paris  green  or 
3  pounds  or  arsenate  of  lead  per  barrel,  preferably  applied  with 
Bordeaux  mixture.  Where  the  plants  are  customarily  sprayed 
with  Bordeaux  mixture  for  leaf  diseases,  arsenites  may  be  added 
and  will  probably  control  this  and  other  strawberry  pests.  Badly 
infested  fields  should  be  plowed  under  deeply  as  soon  as  the  crop 
is  secured  and  new  beds  should  l^e  planted  at  some  distance  from 
them. 

The  Strawberry  Saw-fly  * 

Occasionally  the  strawberry  leaves  are  skeletonized  by  yellow- 
ish or  greenish  "  worms  "  one-half  to  three-quarters  of  an  inch 
long  when  full  grown.     The  head  is  yellow  with  two  brown  spots 


Fig.  322. — The  strawberry  saw-fly  (HarpipJuyrus  maculatus  Norton):  1,  2, 
pupa;  3,  5,  adult  flies:  4,  6,  larvse;  7,  cocoon;  9,  egg — all  enlarged. 
(After  RUey.) 

on  the  side  and  one  or  two  on  top,  and  there  are  eight  pairs  of 
yellowish   abdominal   prolcgs,   in   addition  to   the   true  thoracic 

*  Harpiphorns    maculatus    Norton.     Family    TentJiredinidoe.     See    J.    M 
Stedman,  Bulletin  54,  Mo.  Agr.  Exp.  Sta. 


INSECTS  INJLlRlUlJS  TO  THE   STRAW Bl-^RUV  451 

legs,  which  at  oiu-c  distinguish  the  stiw-fly  larvae  from  true 
caterpillars.  The  adult  saw-flies  are  about  one-quarter  inch 
long,  with  two  pairs  of  l)lackish,  well-veined  wings  which  are 
folded  over  the  abdomen  when  at  rest.  The  body  is  l^lack,  with 
a  row  of  lighter  spots  on  either  side  of  the  al^domen.  The  flies 
emerge  in  late  April  in  Missouri  or  about  a  fortnight  before  the 
plants  flower  freely.  The  eggs  are  inserted  just  beneath  the 
epidermis  of  the  leaves  and  hatch  in  about  two  weeks,  just  as  the 
plants  begin  to  bloom.  The  larvae  eat  holes  in  the  leaves  and 
"  where  numerous,  they  will  defoliate  the  plants  to  such  an  extent 
as  to  greatly  injure  or  completely  destroy  the  crop  of  fruit,  and 
may  even  kill  the  plants  themselves."  When  at  rest  or  disturbed 
the  larvae  coil  themselves  up  in  a  spiral  on  the  under  side  of  the 
leaf  as  shown  in  Fig.  322,  but  if  suddenly  disturbed  they  will  often 
drop  to  the  ground.  By  the  last  of  May  the  larvae  are  full  grown 
and  enter  the  soil,  where  they  make  small  cells,  lined  with  a 
gummy  substance,  and  in  them  hibernate  until  the  next  spring, 
when  they  pupate  and  the  adult  flies  emerge. 

Injury  by  the  saw-fly  has  been  reported  from  the  northern  and 
central  States  from  Missouri  and  Nebraska  to  Maine. 

A  nearly  related  species  *  with  almost  identical  habits  has  done 
similar  injury  in  Iowa,  Illinois  and  Indiana.  The  larvae  are  a  deep 
green,  much  wrinkled,  with  a  blackish  stripe  along  the  back  and 
an  obscure  blackish  stripe  on  each  side,  and  the  head  Ijrown. 

Control.     Inasmuch  as  the  larvae  commence  to  hatch  just  as 

blooming  commences  Professor  Stedman  has  shown  by  experiments 

that  spraying  the  foliage  at  this  time  with  arsenicals  will  entirely 

protect  it  from  the  larvae.     If  they  commence  work  before  their 

presence  is  noticed,  the  foliage  may  be  sprayed  until  the  first 

berries  are  about  one-third  grown  without  any  danger  of  poisoning 

them.    Hellebore  1  pound  to  3  gallons  of  water  was  also  effective, 

as  was  dusting  with  pyrethrum.     Although  there  may  be  some 

prejudice  against  the  use  of  arsenicals,  where  properly  applied 

at  the  right  time  there  is  no  reason  why  they  should  not  be  used. 

*  Monostegia  ignota  Norton.  See  F.  W.  Mally,  "  Insect  Life,"  Vol.  II, 
p.  137. 


452        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Strawberry  Leaf-roller  * 

Where  leaves  are  fouiul  folded  together,  many  of  them  being 
dry  and  brown,  the  small  green  caterpillars  found  feeding  within 
the  folds  are  probably  those  of  the  Strawberry  Leaf -roller.  It 
is  a  European  insect,  though  it  is  not  injurious  there,  and  the 
first  record  of  injury  in  this  country  was  made  by  Dr.  C.  V.  Riley 
in  1869,  who  stated  that  in  one  place  in  Missouri  it  destroyed 
ten  acres  so  completely  as  to  not  leave  enough  plants  to  set  a 
half  acre.  "  Since  that  time,"  says  Dr.  J.  B.  Smith,  "  the  insect 
has  been  frequently  mentioned  as  injurious  in  many  parts  of  the 
country,  but  rarely  is  it  troublesome  for  more  than  a  year  or  two 


Fig.    323. — The   strawberry   leaf-roller   moth    {Ancylis   comptana   Frohl.) — 
enlarged.     (After  J.  B.  Smith.) 

in  succession.     It  is  always  inclined  to  be  local  and  its  ravages 
do  not  often  extend  over  wide  areas." 

Life  Histort/.  The  moths  aj^pear  in  the  strawberry  fields 
during  early  May  in  New  Jersey  and  commence  to  lay  eggs,  the 
moths  being  found  in  the  fields  for  about  a  month.  The  eggs  are 
laid  on  the  under  surface  of  the  half-grown  leaves.  They  are 
]:)roadly  oval  or  round,  much  flattened,  of  a  pale  green  color  and 
about  one-fiftieth  inch  in  diameter.  They  are  laid  in  the  fine 
netting  of  the  leaf,  in  which  they  are  seen  with  great  difficulty. 
The  larva?  hatch  in  from  five  to  seven  days.  The  young  cater- 
pillar feeds  on  the  upper  surface  of  the  leaf  for  a  day  or  two,  eating 
into  and  along  the  midrib  to  weaken  it.     The  young  larva  is  at 

*  Ancylis  comptana  Frohl.  Family  Tortricidce. ,  See  J.  B.  Smith,  Bulletins 
149  and  225,  N.  J.  Agr.  Exp.  Sta. 


INSECTS  INJURIOaS  TO  THE   STRAWBERRY 


453 


finst  a  light-green  color  with  u  large  head  and  long  hair,  which 
becomes  less  noticeable  as  it  grows. 

It  soon  commences  to  draw  the  edges  of  the  leaf  together, 
folding  the  upper  surface  on  the  midrib,  holding  it  together  by 
numerous  strands  of  fine  silk.  The  insect  then  spins  a  partia 
tube  or  lining  inside,  in  which  it  remains  until  the  moth  develops. 
Unless  disturbed  the  larva  does  not  leave  this  folded  leaf,  and  all 


Fig.  324.— Strawberry  leaf  folded  by  the  leaf-roller.     (After  J.  B.  Smith.) 

the  feeding  is  done  out  of  the  reach  of  sprays.  The  larva  becomes 
full  grown  in  about  four  weeks,  when  it  is  about  half  an  inch  long 
and  of  a  dark-green  color,  until  just  before  pupation,  when  it 
becomes  more  yellowish.  The  head  and  thoracic  shield  are 
shining  brown,  and  the  small  body  tubercles  are  slightly  lighter. 
The  larvae  are  slender  and  very  active,  wriggling  violently  when 
disturbed  or  taken  from  their  webs. 


454      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

"  Pupation  occurs  in  the  tube  made  by  the  larva.  The  pupa 
itself  is  brownish-yellow,  without  obvious  processes  or  protuber- 
ances, and  a  little  more  than  one-fourth  an  inch  long."  The  pupal 
stage  lasts  about  ten  days,  thus  giving  about  forty-two  to  fifty 
days  for  the  complete  life  cycle  from  egg  to  adult. 

The  moths  of  the  second  brood  appear  late  in  June  and  during 
July.  This  brood  is  much  more  abundant  on  blackberry  and 
raspberry  than  on  strawberry  plants.  The  moths  of  the  third 
brood  appear  in  August.  They  are  comparatively  few  in  number 
and  also  seem  to  prefer  blacklierr}-  and  raspberry.  Young  larvae 
are,  however,  to  be  found  on  strawberries  in  September.  ''  Accord- 
ing to  the  account  given  by  Riley,  the  larva)  change  to  pupa 
late  in  September  and  remain  during  the  winter  in  that  state." 
Dr.  Smith  states  that  he  has  not  observed  this  personally.  In 
Delaware  we  have  found  full-grown  larva)  in  folded  leaves  in 
midwinter,  so  that  possibly  some  of  them  at  least  do  not  pupate 
until  spring. 

''  The  adult  moth  is  small,  measuring  with  expanded  wings 
about  two-fifths  of  an  inch.  In  general  color  it  is  somewhat 
reddish-brown,  the  fore-wings  streaked  and  spotted  with  black  and 
white  as  shown  in  the  illustration.  When  the  wings  are  folded, 
the  dark  area  at  the  base  forms  a  somewhat  conspicuous  deeper 
brown  patch  in  the  middle  of  the  back.  The  hind-wings  are  of 
a  soft,  dark  smoky  gray,  and  both  wings  have  long  fringes.  The 
insects  fly  readily  during  the  middle  of  the  day,  and  run  rapidh' 
on  the  leaves,  diving  to  the  under  side  or  into  a  fold  so  quickly 
that  it  requires  close  watching  to  follow  their  movements. 
From  the  fact  that  newly  set  fields  are  often  infested,  it 
is  probable  that  they  fly  for  some  distance  to  seek  their  food 
plant." — Smith. 

"  A  badly  infested  strawberry-patch  begins  to  look  scorched 
early  in  June,  and  before  the  middle  of  that  month  appears  as  if 
a  fire  had  been  over  it.  The  fruit,  deprived  of  the  food  prepared 
by  the  foliage,  stops  growth,  ripens  undersized  or  prematurely,  or 
shrivels  up  altogether,  even  before  it  colors."  "  Often  every 
lobe  on  a  leaf  will  be  folded,  and  occasionally,  when  infested 


INSECTS   INJURIOUS  TO   THE  STRAWBERRY  455 

leaves  cover  or  touch,   an  irregular  mass  of  foliage  is  bundled 
up  in  which  as  many  as  six  or  eight  larva3  may  be  found. 

"  On  blackberry  not  so  large  a  part  of  the  leaf  is  involved, 
and  frequently  only  the  tip  of  one  of  the  leaflets  is  webbed  up. 
Furthermore,  the  injury  is  more  local,  and  only  that  part  that 
is  actually  eaten  is  harmed.  The  total  amount  of  food  really 
devoured  is  very  small,  and  were  it  not  for  the  manner  of  feeding 
which  interferes  with  the  nutrition  of  the  leaf,  the  strawberry 
could  easily  spare  tissue  for  all  these  caterpillars  that  ever  infect 
it.  On  the  raspberry  the  habit  is  yet  different.  Here  the  larva 
gets  into  a  partly  opened  tip  and  webs  it  together  so  securely 
as  to  check  growth.  The  actual  eating  shows  a  rusty  space  on 
the  upper  side  of  the  leaf,  and  not  much  more  harm  is  done." 

Control. — As  stated  above,  the  young  caterpillar,  just  after 
It  is  hatched,  goes  to  the  upper  surface  of  the  leaf  and  feeds  there 
exposed  for  a  day  or  two  before  folding  the  leaf.  "  It  must  be 
the  object  of  the  grower  to  poison  the  foliage  so  early  in  the  season 
that  when  the  young  caterpillar  starts  feeding,  it  can  find  no 
foliage  it  can- safely  eat.  Therefore,  as  soon  as  moths  are  found 
flying  in  fair  numbers,  spray  with  Paris  green,  or  some  other 
arsenite  (preferably  arsenate  of  lead).  As  the  plants  grow 
rapidly,  spray  again  a  week  later,  and  a  third  time  a  week  there- 
after. This  will  catch  the  great  bulk  of  the  caterpillars  that  will 
become  injurious  in  June,  leaving  only  a  very  few  that  hatch 
late  and  cannot  cause  much  harm.  A  single  spraying  will  do 
comparatively  little  good,  because  the  moths  extend  the  egg- 
laying  period  over  so  long  a  time.  The  first  larvse  are  almost 
full  grown  before  the  last  eggs  are  hatched." 

"  If  for  any  reason  no  timely  applications  were  made  and  the 
fields  become  badly  infested,  nothing  practical  can  be  done  until 
the  crop  is  off.  Then  mow  the  beds,  rake  off  all  the  foliage,  and 
burn  it.  You  will  burn  with  it  all  the  larvae  and  pupae  that  are 
then  unchanged.  This  lessens  the  number  of  moths  that  come 
to  maturity  and  so  helps  somewhat  for  the  following  year." 

"  On  blackberry  and  raspberry  no  remedial  measures  have 
proved  necessary  so  far.     If  there  are  many  caterpillars  present 


456       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

late  ill  the  suiiuner  it  may  pay  to  haiidpick  all  infested  leaves 
or  to  crush  the  larva  in  the  folded  leaf.  This  will  tend  to  lessen 
the  number  that  live  over  winter." 


The  Strawberry  Weevil  * 

If  the  buds  appear  to  be  "  stung  "  so  that  they  wither,  and 
if  many  of  the  stems  are  3ut  so  that  the  buds  drop  to  the  ground, 
the  strawberry  weevil  is  the  probable  cause  of  the  damage.  This 
little  weevil  is  only  about  one-tenth  inch  long  and  so  is  often 
unnoticed,  and  the  loss  is  attributed  to  other  causes.  The  weevil 
varies  from  nearly  black  to  dull  red,  with 
a  dark  spot  just  back  of  the  centre  of 
each  wing-cover.  The  head  is  prolonged 
into  a  slender  curved  snout,  about  half 
as  long  as  the  body.  The  species  is 
found  in  most  of  the  States  east  of  the 
Rockies,  but  injury  has  been  most  severe 
in  the  Middle  and  Northern  States. 

Life  History. —  The  weevils  hibernate 
over  winter  and  appear  in  spring  a  few 
days  before  the  earliest  staminate  vari- 
eties commence  to  bloom.  Others  emerge 
during  the  next  month,  ])ut  the  most 
injury  is  tlone  within  the  next  two  weeks. 
The  injury  is  done  l)y  the  females,  which 
eat  small  holes  through  the  outer  husk 
or  corolla  of  nearly  matured  buds,  and  in 
these  little  cavities  deposit  their  eggs. 
Dept.  Agr.)  The  stem  of  the  bud  is  then  cut  so  that  it 

hangs  by  a  mere  thread  and  soon  falls  to  the  ground.  By  severing 
the  stem  the  development  of  the  bud  is  arrested,  thus  preventing 
the  outer  covering  from  unfolding  and  holding  the  eggs  and  larva? 
in  the  pollen,  on  which  they  feed,  and  by  falling  to  the  ground 

*  Anthonomus  signatus  Say.  Family  Curculionidce .  See  F.  H.  Chittenden, 
Circular  21,  Div.  Ent.,  U.  S  Dept.  Agr.;  J.  B.  Smith,  Bulletin  225,  N.  J. 
Agr.  Exp.  Sta. 


Fig.  325.— The  straw- 
berry weevil  {Antho- 
nomus signatus  Say) — ■ 
enlarged.  (After  Riley 
and  Chittenden,  U.  S. 


INSECTS  INJURIOUS   TO   THE  STRAWBERRY 


457 


the  bud  reniiiins  moist  and  will  not  dry  up  as  it  would  on  the  stem. 
The  eggs  hatch  in  from  six  to  seven  days  and  the  small  whitish 
larvae  feed  on  the  pollen  and  later  on  the  harder  parts  of  the  buds. 
Three  or  four  weeks  are  required  for  a  larva  to  become  full  grown. 
It  then  forms  a  little  cell  in  the  bud,  in  which  the  pupal  stage  is 
passed  in  from  five  to  eight  days,  when  the  adult  beetle  emerges 
and  cuts  its  way  out.  Thus  the  complete  life  cycle  occupies 
about  a  month  and  in  the  District  of  Columbia  the  new  generation 
of  beetles  appears  during  June.     They  are  frequently  found  in 


Fig.  326. — The  strawberry  weevil:  a,  b,  spray  showing  work  in  bud  and  stem — 
natural  size;  c,  outhne  of  egg;  d,  larva;  e,  head  of  same;  /,  pupa;  g, 
bud  opened  to  show  egg  on  left  and  punctures  made  by  snout  of  beetle 
through  petals.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

large  numbers  on  strawberry  flowers  and  on  those  of  the  horse 
mint  (Monarda  fistulosa),  but  the  beetles  soon  seek  hibernating 
quarters,  there  being  but  one  generation  a  year. 

Control. — As  the  larva?  feed  upon  the  pollen  of  the  buds  of 
staminate  varieties,  the  staminate  varieties  are  most  injured, 
and  injury  may  be  avoided  by  growing  as  few  rows  of  staminate 
varieties  as  are  necessary  for  fertilizing  the  rest  of  the  bed.  Indeed 
the  very  early  staminate  varieties  might  iDe  used  as  a  trap  crop 
for  attracting  the  weevils,  which  might  be  destroyed  by  covering 
the  rows  with  sti'aw  and  l)urning,  or  possibly  by  spraying  with 


458        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD     • 

arsenicals.  By  planting  rows  of  early  varieties,  which  flower 
freely  and  produce  an  abundance  of  pollen  near  woods  and 
fence-rows  where  the  l:)eetles  have  hibernated  and  appear  first, 
they  might  be  effectively  trapped,  and  then  destroyed.  Although 
the  larvse  cannot  be  reached  with  any  insecticide,  the  beetles 
feed  more  or  less  on  the  buds  and  foliage,  and  further  experiments 
should  be  made  in  spraying  for  them  with  arsenicals.  In  view  of 
the  recent  success  in  the  use  of  arsenate  of  lead  against  the  plum 
curculio,  we  would  suggest  the  thorough  spraying  of  badly  infested 
beds  with  arsenate  of  lead  3  to  5  pounds  per  barrel,  applying  it 
with  an  under-spray  nozzle  so  as  to  thoroughly  cover  every  bit 
of  foliage.  This  should  be  applied  as  soon  as  the  buds  commence 
to  form  and  probably  a  week  later  Ijefore  they  blossom,  as  it  is 
then  that  the  beetles  are  feeding.  Spraying  at  that  season  can  do 
no  possible  harm  to  the  berries,  and  to  spray  after  the  buds  are 
injured  is  useless.  The  destruction  of  all  trash  and  rul)l)ish  in 
and  around  the  fields  during  the  winter  will  destroy  some  of  the 
hibernating  weevils,  and  it  will  be  well  to  avoid  mulching  the 
beds  where  the  beetle  is  troublesome,  if  the  mulch  is  not  abso- 
lutely necessary,  as  it  furnishes  them  the  best  hibernating 
quarters. 


CHAPTER  XXIII 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY* 


The  Raspberry  Root-borer  t 

The  larvae  of  the  Raspberry  Root-borer  make  tunnels  in  the 
roots  and  lower  stems  of  raspberry  and  blackberry,  sometimes 
completely  girdling  the  stem  at  the  crown,  so  that  the  name  of 
blackberry  crown-bor^n-  has  also  been 
used.  The  full-grown  larva  is  from  1  to 
1^  inches  long,  yellowish -white,  with 
brownish  head,  and  the  tips  of  the  small 
thoracic  legs  also  browaiish.  The  parent 
insect  is  one  of  the  clear-winged  moths, 
which  fly  by  day  and  closely  resemble 
wasps,  and  is  nearly  related  to  the  peach- 
and  squash-borers.  The  female  is  much 
the  larger  and  is  shown  natural  size  in 
Fig.  328.  The  body  is  black  with  yellow 
rings,  and  the  legs  are  yellowish.  The 
w^ings  are  transparent  except  a  bronze- 
brown  margin  and  a  narrow  band  across 
the  fore-wings  about  one-third  from  the 
tip. 

Life  History. — The   moths   appear  in 
late  August  and  September  and  the  females  deposit  their  eggs 
upon  the  lower  edge  of  the  leaves.     The  egg  is  oval,  about  one- 

*  See  F.  M.  Webster,  Bulletin  45,  Ohio  Agr.  Exp.  Sta.;  J.  B.  Smith,  12th 
Report  N.  J.  Agr.  Exp.  Sta. 

•j-  Bembecia  marginata  Harr.  Family  Sesiidce.  See  J.  B.  Smith,  Bulletin 
N,  N.  J.  Agr.  Exp.  Sta.,  p.  9;  W.  H.  Lawrence,  Bulletin  63,  Wash.  Agr.  Exp. 
Sta. 

4."9 


Fig.  327. — The  raspberry 
root-borer  (Bembecia 
marginata  Harr.)  :  a, 
male  moth;  b,  female 
moth  —  natural  size. 
(After  Riley.) 


460         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


\* 


sixteenth  inch  long,  deep  brownish-red  in  color.  A  female  lays 
about  140  eggs,  which  are  deposited  singly.  They  hatch  in  Sep- 
tember and  the  young 
larvae  crawl  down  the 
stems  and  bore  under  the 
bark.  Here  they  may 
either  make  a  small  blis- 
ter-like cavity  and  hiber- 
nate over  winter,  or  if 
hatched  earlier  they  may 
feed  on  the  sap  wood  or 
occasionally  bore  into  the 
stem  and  become  onc?- 
quartcr  inch  or  more  long 
before  winter.  The  next 
season  the  larvae  bore 
in  the  lower  stem  and 
roots,  but  the  nature 
of  the  injury  differs 
as  observed  in  different 
places.  In  New  Jersey, 
Dr.  J.  B.  Smith  states 
that  the  larvae  girdle  the 
stem  at  the  crown,  caus- 
ing the  plants  to  die.  In 
spring  they  abandon  the 
old  wood  and  attack  new 
shoots,  but  he  observed 
none  entering  the  stems. 
In  Washington,  the  in- 
fested plants  seldom 
show  any  signs  of  the 
presence  of  the  borers 
other     than     a     poor 


d 
Fig.  328. — Raspberry  root-borer  (Bembecia 
marginata  Harr.):  a,  female  and  male 
larvae  full  grown;  6, male  and  female  pupa-; 
c,  female,  and  (/,  male  moths  resting  on 
leaf;  e,  e,  eggs — slightly  reduced.  (After 
Lawrence.) 


growth,  though  occasionally  a  few  hills  will  die  where  the  roots  have 
been   badly  i-iddlod  l)y  th(^  larvae,  the  injury  ho'n\^  mostly  in  the 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY       461 

I'oots.  "  The  boi'cr,"  according  to  Lawrence*,  "  first  enters  the  roots 
and  tunnels  tlirough  them  proniiscuousl}-  until  the  second  spring, 
and  then  directs  its  course  upward,  entering  and  eating  the  pith  of 
the  cane  for  a  distance  of  one  to  five  inches."  At  the  end  of  the 
first  summer  the  hirva  is  one-half  to  three-quarters  inch  long.  By 
the  middle  of  the  second  summer  the  larva  is  full  grown  and 
bores  an  exit  hole  through  the  wood  and  bark  just  above  the 
crown,  leaving  the  hole  covered  by  the  epidermis  only.  The 
larva  then  descends  into  the  tunnel  and  pupates. 

The  pupa  is  about  three-quarters  inch  long,  reddish-brown,  the 


Fi(i.  329. —  Woik  of  the  rasi)beiTy  root-borer:  a,  two  eanes  with  empty  pupa 
cases  ])rojecliiifi;  i'roiii  burrows;  h,  canes  showiiij^  opening  of  tunnel 
throufih  wliich  pui)a'  have  wriggled  out.     (After  Lawrence.) 

head  bears  a  sharp-pointed  process,  and  each  abdominal  segment 
bears  two  transverse  rows  of  sharp  teeth.  By  means  of  these  the 
pupa  wriggles  itself  out  of  the  burrow  until  it  projects  from  the 
aperture,  and  the  adult  moth  emerges.  This  insect  occurs  through- 
out the  Middle  and  Northern  States  east  of  the  Rockies,  is  injurious 
in  Washington  and  around  Vancouver,  B.C.,  and  has  been 
observed  in  Colorado  and  New  Mexico. 

Control. — The  only  method  of  control  is  to  pull  up  the  infested 
canes,  root  and  branch,  and  destroy  them  ])y  Ixirning.  As  this 
is  the  only  means  of  controlling  several  pests  of  cane  fruits,  the 


462      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

canes  should  always  be  gone  over  in  spring  and  those  showing 
any  injury  examined  and  removed  if  affected. 


The  Raspberry  Cane-borer  * 

If  the  tips  of  the  young  shoots  of  raspberry  and  blackberry 
are  found  withered  and  dying  they  have  prol^al^ly  been  girdled 
by  the  cane-borer.  The  adult  beetle  is  about  one-half  inch  long 
with  a  slender,  cylindrical  body  and  long  antenna^,  and  of  a  deep 
black  color  except  the  prothorax,  which  is  yellow  with  two  or 
three  black  spots,  though  these  are  sometimes  lacking. 

Life  History. — The  beetles  appear  in  early  summer  and  the 
females  girdle  the  young  tips  by  cutting  two  rings  around  the 


Fig.  330. — The  raspberry  cane-borer  (Oberea  bimaculata  Oliv.):   adult,  larva, 
and  larval  castings — all  enlarged.     (After  Lugger.) 

shoot  about  an  inch  apart,  causing  the  tip  to  wither  and  droop. 
Between  these  rings  will  be  found  a  small  dark  spot  where  the 
female  has  inserted  an  egg  in  the  cane.  A  rather  large,  elliptical, 
yellow  egg  is  placed  in  the  pith  of  the  cane  and  in  a  few  days 
hatches  into  a  small  white  grub.     The  larvae  burrow  downward 

*  Oberea    bimaculata    Oliv.     Family    Cerambycidce.     See    Comstock    and 
Slingerland,  Bulletin  23,  Cornell  Univ.  Agr.  Exp.  Sta.,  p.  122. 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY      463 

through  the  pith  of  the  stems,  the  burrows  winding  from  side 
to  side  and  frequently  penetrating  the  side  of  the  stem,  where 
openings  are  made  every  few  inches,  through  which  long  strings 
of  excrement  are  cast  out.  By  fall  they  have  bored  to  the  base 
of  the  cane,  in  which  they  hibernate  over  winter.  The  full- 
grown  larva  is  about  one  inch  long,  of  a  dull  yellow  color,  with 
a  small  dark-brown   head.     The  body   is  quite    cylindrical  and 


'^ . 

■m 

Fig.  331. — Egg  of  the  rasp- 
berry cane-borer,  showing 
girdling  of  cane.  (Photo 
by  Headlee.) 


Fig.  332. — Young  grubs  and  exit  hole 
of  the  raspberry  cane-borer.  (Photo 
by  Headlee.) 


the  segments  constricted  as  shown  in  Fig.  330.  The  pupal  stage  is 
passed  in  the  burrow  during  the  spring.  Although  it  has  been  gen- 
erally assumed  that  the  life  cycle  is  passed  in  a  single  year,  there  is 
some  reason  for  believing  that  two  years  may  be  required.  The 
eggs  are  usually  laid  only  in  the  young  tips,  but  Comstock  and 
Slingerland  found  larva?  somewhat  over  half  grown  which  had  made 
burrows  only  two  inches  long  in  old  canes  in  late  July,  and  Professor 
Webster  has  secured  larvse  over  half  grown  in  early  June.    Possibly, 


464        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


therefore,  two  years  may  be  required  for  maturing  a  generation, 
and  the  fact  that  the  pest  does  not  increase  may  be  due  to  the 
cutting  back  of  the  injured  tips  of  the  young  canes. 

Control. — As  soon  as  the  tips  are  seen  to  droop  they  should 
be  cut  off  below  the  point  girdled  and  burned.  When  the  entire 
canes  die  from  the  effect  of  being  tunneled,  they  should  be  cut 
in  late  summer  before  the  larvse  have  gone  to  the  base  to  hiber- 
nate. Where  such  measures  are  practised  the  pest  may  be  effec- 
tively controlled. 

The  Snowy  Tree-cricket  * 

When  the  canes  fail  to  put  out  leaves  in  the  spring  and  are 
found  to  be  dead,  this  often  proves  to  be  due  to  a  long  ragged 
wound  like  that  shown  in.  Tig.  334a.  "If  the  rough  surface  of 
the  wound  be  cut  away' with  a  knife,  the  injury  will  be  found  to 
consist  of  a  longitudinal  series  of  punctures  placed  close  together. 
By  splitting  the  cane  the  nature  of  the  injury  can  be  seen  even 
better. 


Such  a  section^ssli^n  at  b  in  the  figure.     The  punctures 

:#^';^:^xtend  through  the  woody  part  of 

the  cane  into    the    pith,  and   here 

there  is  in^  each   an   oblong,  cylin- 

^,  drical   egg.'     One  of   these   eggs  is 
-  ■  i  '  . 

.:*;' represented   enlarged    at'   c.      The 

insect  which  thus  seriously  injures 

the  raspberry  canes    in    preparing 

a    safe    receptacle    for    its   eggs  is 

a    delicate    greenish-white    cricket. 

On    account    of   its    color  and   its 

habit    of   living   among  the  foliage 

of  trees  and  shrubs,  it  has  received 

the   popular  name   of    the    Snowy 

Tree-cricket.     Fig.  3336  represents  the  male.     Its  wing-covers  are 

crossed  by  oblique  thickenings  or  ribs,  which  form  part  of  the  musi- 

*  (Ecanthus  niveus  DeG.  Family  Gryllida;.  See  Comstock  and  Slinger- 
land,  Bulletin  23,  Cornell  Univ.  Agr.  Exp.  Sta.,  p.  124;  H.  O.  Houghton, 
Entomological  News,  Vol.  XIV,  p.  57. 


Fig.  333.— The  snowy  tree- 
cricket  (Oecanthus  niveus  De 
G.):  a,  female;  6,  male — en- 
larged.    (After  Summers.) 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY       465 


('111  apparatus  of  tlic  insect.  The  female,  Fig.  333a,  differs  some- 
what in  appearance  from  the  fact  that  the  wing-covers  are  wrapped 
closely  about  the  body,  making  the  insect  much  narrower  than 
her  mate."  (Comstock  and  Slingerland,  I.e.)  The  cry  of  these 
tree-crickets  is  well  known,  sounding  much 
like  that  of  the  katy-did,  but  is  less 
rasping  and  more  monotonous.  They  are 
heard  in  early  evening'  until  well  into 
the  night,  and  in  the  North  their  chirp 
is  the  most  noticeable  of  all  the  insect 
noises  at  that  time.  This  species  is 
cjuite  widely  distributed  and  frequently 
oviposits  in  the  tender  twigs  of  fruit 
trees,  which  are  similarly  injured,  and 
in  the  stalks  of  cotton  and  various  •\voody 
weeds. 

Life  History. — The  eggs  are  laid  in  the 
fall  and  hatch  in  the  late  spring.  The 
nymphs  feed  mostly  on  plant-lice  and 
other  insects,  as  do  the  adults,  and  though 
they  occasionally  nibble  foliage,  they  are 
never  injurious,  and  both  nymphs  and 
adults  must  Ije  regarded  as  beneficial  as 
far  as  their  feeding  habits  luv  conc(>rned. 
In  the  North  tli(>  uynij)hs  Ix-conic  full 
gi'own  late  in  July,  and  therc^  is  but  one 
generation  a  3'ear,  l)ut  in  Texas  they 
l^ecome  full  grown  late  in  June  and  eggs 
laid  in  early  July  hatch  in  about  two  weeks; 
n}-mphs  are  common  in  late  summer,  and 
the  adults  of  the  second  generation  in  fall. 

Control.  —  By  examining  the  canes  as  soon  as  the  foliage 
starts,  those  injured  may  be  detected  and  should  be  cut 
out  and  burned.  If  not  numerous  enough  to  do  appreciable 
damage  they  may  be  ignored. 


Fig.  334. — Raspberry 
stem  injured  by  the 
snowy  tree-cricket  : 
a,  wound  made  by 
egg  -  jjimctures  ;  b, 
longitudinal  section 
through  same  show- 
ing eggs  in  pith;  c, 
egg  enlarged ;  d,  cap 
of  egg,  more  enlarged . 
(After  Riley.) 


466        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Red-necked  Cane-borer  * 

Sometimes  the  canes  of  raspberry  and  blackberry  are  found 
with  one  or  more  elongate  galls,  not  over  one-third  larger  in 
diameter  than  the  normal  cane,  and  usually  with  numerous  slits, 
which  have  been  called  the  "  gouty  gall."     The  infested  shoots 


Fig.    335. — The   red-necked    cane-borer    {Ai,r'lHS    ruficollis    Fab.):     beetle, 
larva,  and  gall — all  much  enlarged.     (After  Riley.) 

may  throw  out  leaves,  but  they  rarely  ripen  fruit  and  usually  die 
during  the  season.  By  opening  the  gall  it  will  be  found  that  only 
the  bark  has  been  injured  by  a  spiral  channel  which  girdles  the 
stem  and  causes  the  gall-like  thickening  of  the  bark.  Above 
the  swelling  evidence  will  be  found  of  the  borer's  work  in  the 

*  Agrillus  ruficollis  Fab.   Family   Buprestidoe.     See    J.    B.    Smith,    12th 
Rsport,  N.  J.  Agr.  Exp.  Sta.,  p.  373;  and  F.  M.  Webster,  I.e.,  p.  191. 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY      467 

pith,  and  from  one  to  six  inches  above  the  gall  the  slender  white 
larva  will  be  found  at  work. 

There  seems  to  be  considerable  difference  in  the  susceptibility 
of  varieties,  Dr.  Smith  oloserving  that  the  "  Wilson  "  and  black- 
cap raspberries  are  badl}'  infested,  while  the  "  Missouri  Mammoth  " 
and  others  were  unharmed. 

Life  History. — The  eggs  are  laid  in  June,  but  have  not  been 
ol^served.  Whether  laid  on  the  stalk  or  on  a  leaf,  the  young  larva 
enters  the  bark  at  the  axil  of  a  leaf-stem,  and  eats  around  the 


Fig.  336. — Work  of  the  red-necked  cane-borer:  a,  tracks  of  young  larvae, 
the  bark  shced  away  to  show  burrows  and  forming  gall  ridges;  h,  section 
through  galls  on  main  cane  and  lateral  showing  track  of  larva  through 
bark  and  pith  and  pupal  cell.     (After  .J.  B.  Smith.) 

stem  in  a  long  spiral.  By  early  August  the  galls  commence  to 
form  where  the  bark  has  been  girdled,  though  sometimes  no  gall 
results  from  the  injury,  and  the  larvae  mine  into  the  pith.  The 
larva?  probably  become  practically  full  grown  in  the  fall  and  remain 
in  their  burrows  over  winter,  in  which  they  transform  to  pupae 
in  late  April,  in  New  Jersey,  and  the  beetles  emerge  in  late  May 
and  June.  The  parent  beetle  is  not  over  one-third  inch  long, 
flattened,  with  a  small  wide  head,  and  tapers  at  the  tip  of  the 
abdomen.  It  has  brownish-black  wing-covers  with  a  bronzy 
lustre,  and  the  neck  and  thorax  are  coppery-red  or  brassy.     The 


468        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


full-grown  larva  is  five-eighths  to  three-quarters  inch  long,  with 
a  small  brown  head,  a  much-expanded  prothorax  which  looks 
like  the  head,  and  a  slender,  cylindrical,  white  body,  surmounted 
by  two  slender  brown  horns  at  the  tip  of  the  abdomen. 

This  cane-borer  is  a  native  pest,  very  common  in  wild  raspberries 
and  blackberries,  and  occurs  generally  throughout  the  country. 

Control. — Obviously  it  may  be  readily  controlled  by  cutting  off 
the  infested  canes  below  the  galls  and  burning  them.  This  should 
be  done  any  time  before  May.  Where  wild  canes  are  infested 
near  those  cultivated  they  should  be  included  in  the  pruning. 

The  Blackberry  Gall-maker  * 

The  so-called  ''  pithy  gall  "  of  the  blackberry  is  an  elongated. 


Fig.  337. — The  pithj'-gall  of  the  blackberry :  a,  gall ;  h,  section  of  same  showing 

larvae  in  cells;  c,  larva  enlarged  and  natural  size;  d,  pupa.     (After  Riley.) 

*  Diastrophus  turgidus  Bass.     Family  Cynipidce. 


INSECTS  INJURIOUS  TO  RASPBERRY  AND  BLACKBERRY      469 

pithy  swelling  from  one  to  three  inches  long  and  nearly  an  inch 
in  diameter,  red  or  reddish-brown,  with  the  surface  divided  by 
deep  longitudinal  furrows  into  four  or  five  ridges  or  parts.  The 
gall  is  caused  by  the  larvae  of  a  small  black  gall-fly,  which  is 
about  one-twelfth  inch  long,  with  red  feet  and  antennae  and  four 
transparent  wings,  almost  lacking  wing-veins.  The  insect  passes 
the  winter  in  the  larval  stage  in  the  galls,  and  if  one  be  opened 
at  that  season,  there  will  be  found  al)Out  the  middle  a  number  of 
cells  about  one-eighth  inch  long,  each  of  which  contains  a  single 
larva.  The  larva  "  is  about  one-tenth  inch  long,  white,  with  the 
mouth-parts  reddish,  and  the  breathing  pores  and  an  oval  spot 
on  each  side  behind  the  head  of  the  same  color."  They  change 
to  pupse  in  spring  and  the  flies  appear  a  little  later.  Though 
this  gall  is  also  very  common  on  wild  canes  it  rarel}^  does 
much  injury. 

Control. — The  affected  canes  should  be  cut  and  burned  during 
the  winter. 

The  Raspberry-cane  Maggot  * 

The  tips  of  young  raspberry  shoots  sometim(\s  droop  and  wilt 
in  the  spring  in  much  the  same  manner  as  W'hen  affected  by  the 
cane-borer  later  in  the  season,  and  though  blackberry  shoots  are 
similarly  affected  they  usually  recover,  but  bear  small  gall-like 
swellings  like  those  shown  in  Fig.  339.  This  is  the  work  of  a  small 
white  maggot,  nearly  related  to  and  looking  much  the  same  as  the 
cabbage-maggot  (p.  347),  which  girdles  the  inner  bark  of  the 
stem.  Injury  has  been  observed  in  New  York,  Canada,  Michigan, 
Pennsylvania,  and  recently  it  has  become  a  serious  pest  in  Wash- 
ington, so  that  it  is  undoubtedly  much  more  widely  distributed 
than  the  records  indicate.  The  parent  fly,  shown  in  Fig.  338, ' 
is  grayish  black,  much  resembling  the  house-fly,  but  slightly 
smaller. 

Life  History. — The  flies  appear  in  .Vpril  and  deposit  their  eggs 
as  soon  as  the  shoots  are  well  above  ground,  continuing  until  early 

*  Phorbia  rubivora  Coquillet.  Family  Antfujmyidce.  See  Slingerland, 
Bulletin  126,  Cornell  Univ.  Agr.  Exp.  Sta.,  p.  54;  W.  H.  Lawrence,  Bulletin 
62.  \\'ash.  Agr.  Exp.  Sta. 


470         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

June.  The  white  egg  (Fig.  338,  c)  is  elongate,  about  one-fifteenth 
inch  long,  and  is  laid  in  the  axil  of  a  young  leaf  at  the  tip  of  a 
shoot  (Fig.  338,  d).     The  egg  hatches  in  a  few  days,  and  the  little 


Fi(i.  338.— The  raspberry  cane-maggot  {Phorhia  r uhivora  CoqwWei) :  a  adult 
female  fly;  much  enlarged;  h,  raspberry  shoots  girdled  by  the  maggot 
natural  size;  c,  egg  much  enlarged;  d,  tips  of  shoots  each  bearing  an  egg 
m  natural  position  in  the  leaf  axils,  natural  size.     (After  Slingerland.)  ° 


INSECTS  INJURIOUS  'I'O  RASPBERRY  AND  BTACUvBERRY      471 

maggot  l)urrows  into  the  pitli  of  the  shoot,  leaving  a  conspicuous 
entrance  hole,  which  Ijeconies  blackish.  It  tunnels  downward, 
making  a  small  tortuous  chann(4,  and  after  boring  for  a  few  days 
about  half  way  down  the  shoot,  it  works  its  way  out  to  just 
beneath  the  bark  and  tunnels  around  the  shoot,  often  in  a  spiral, 
so  as  to  completel}'  girdle  it,  and  usually  eats  a  small  hole  through 
the  bark  at  this  point.  The  maggot  continues  to  feed  on  the 
pith  at  this  point  so  as  to  liearly  sever  the  shoot,  the  tip  of  which 
soon  wilts  and  droops,  turning  a  deep  blue  color.  On  blackberry 
shoots,  however,  the  bark  is  so  thick  that  although  the  tip  droops 


Fig.  339. — Gall-like  swelling  on  living  blackberry  canes  caused  by  the  rasp- 
berry cane-maggot.     (After  LawTence.) 

for  a  few  days,  it  usually  revives  and  the  girdling  forms  a  circular, 
gall-like  swelling,  though  even  blackberries  are  often  killed. 
Affected  shoots  usually  liranch  from  below  the  girdled  point, 
making  a  bushy  growth.  Lawrence  states  that  later  in  the 
season  lateral  shoots  are  also  attacked.  He  also  observes  that 
maggots  never  develop  in  living  canes.  The  maggot  continues 
to  burrow  downward  in  the  pith  and  becomes  full  grown  in  June, 
when  it  pupates  at  the  lower  end  of  the  burrow.  The  puparia 
are  to  be  found  in  the  lower  part  of  the  affected  stalk  in  June 
and  July,  but  the  adult  flies  do  not  emerge  until  the  next  spring. 
Control. — As  soon  as  the  young  tips  are  seen  to  droop  they 


472         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

should  be  cut  off  several  inches  below  the  girdled  point  and 
burned.  This  may  be  done  best  late  in  May  or  in  June  after  all 
the  eggs  are  laid. 

The  Raspberry  Saw-fly  * 

Occasionally  raspberry  leaves,  as  well  as  those  of  blackberry 
and  dewberry,  are  skeletonized  in  May  by  small  green,  spiny 
saw-fly  larvae,  which  sometimes  quite  defoliate  the  plant.  Such 
injury  has  been  commonly  noted  in  the  Eastern  and  Central 
States.  The  adult  female  is  a  typical  saw-fly  about  one-quarter 
inch  long  and  with  a  wing  expanse  of  one-half  inch.  The  body 
and  wings  are  black  except  the  second  to  sixth  abdominal  seg- 
ments, which  are  yellowish-white,  and  the  under  side  is  rusty. 
The  male  is  somewhat  smaller  and  is  entirely  black  except  the 
shoulders,  which  are  yellowish -white. 

Life  History. — The  adults  appear  about  the  middle  of  May 
in  central  New  York,  and  the  females  deposit  their  eggs  late  in 
that  month.  The  eggs  are  inserted  just  under  the  cuticle  of  the 
under  surface  of  the  leaf,  and  the  tissue  around  them  turns 
}-ellowish,  so  that  infested  leaves  soon  Ijecome  spotted  on  the  upper 
surface.  The  egg  is  nearly  pear-shaped,  yellowish-white,  about 
one-twentieth  inch  long,  and  hatches  in  seven  to  ten  days.  As 
many  as  twenty-four  eggs  have  been  observed  in  a  single  leaf,  and 
frequently  the  leaves  are  so  spotted  as  to  l)e  readily  recognized. 
The  young  larva  is  al)out  one-twelfth  inch  long,  yellowish- white 
or  pale  yellowish-green  and  well  covered  with  spiny  tubercles,  the 
spines  being  first  white  and  later  dark  l^rown.  The  young  larvae 
feed  on  the  soft  parts  of  the  leaf,  but  as  they  grow  older  all  but  the 
midrib  and  larger  veins  are  devoured.  The  mature  larva  is  about 
three-quarters  inch  long,  from  light  yellowish-green  to  dark  green, 
closely  simulating  the  color  of  the  foliage,  and  the  body  is  covered 
with  transverse  rows  of  tubercles,  bearing  a  var}'ing  number  of 
strong,  barbed  spines,  which  are  dark  brown  on  the  back  and 
pale  green  or  white  along  the  sides.     The  larva  feeds  for  about  ten 

*  Monophadnus  rubi  Harris.  Family  Tenthredinidce.  See  V.  H.  Lowe, 
Bulletin  150,  N.  Y.  Agr.  Exp.  Sta.. 


^•^■v^ 


s^s 

W^M 

■J    \ 

^^n 

mgg 

c  d 

Fig.  340. — The  raspberry  saw-fly  {Monophadnus  ruhi  Harr.):  o,  male;  h, 
female;  c,  egg  blisters  on  leaf;  d,  larva;  e,  cocoons — all  much  enlarged. 
(After  Lowe.) 

473 


474        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

days  and  then  enters  the  soil  for  from  two  to  three  inches  and 
there  constructs  a  small  oval  cocoon  about  one-third  inch  long, 
which  looks  like  a  pellet  of  earth,  being  formed  of  a  brown  mucilag- 
inous substance,  interwoven  with  coarse  strands  of  silk,  to  which 
particles  of  earth  adhere.  The  larva  then  hibernates  until  the 
next  spring,  when  it  transforms  to  the  pupa  and  in  a  few  days 
the  adult  appears,  usually  early  in  May. 

Control.  —  By  suddenly  jarring  or  shaking  the  bushes  the 
larvffi  will  drop  to  the  soil.  On  light  soils  this  habit  may  be 
utilized  for  their  destruction  Ijy  jarring  them  to  the  ground  and 
following  with  cultivators  so  as  to  l)ury  the  larvae  in  the  loose  soil. 
This  will  Ijc  particularly  applicable  in  hot  weather,  if  the  soil  is 
hot  and  dusty,  when  most  of  the  larva3  will  be  killed  before 
regaining  the  plants.  By  frequent  cultivation  in  late  summer  or 
fall  the  cocoons  might  be  brought  to  the  surface  and  some  of  the 
larvae  might  be  thus  killed  during  the  winter,  though  this  needs 
testing,  as  they  are  fairly  well  protected.  The  lai-va  may  be 
readily  killed  with  arsenical  sprays,  and  if  arsenate  of  lead  were 
applied  at  the  rate  of  3  pounds  per  barrel  just  as  the  plants 
commence  to  flower,  it  would  undoubtedly  control  the  pest  with 
no  possibility  of  spotting  the  fruit,  or  Paris  green  with  Bordeaux 
mixture  might  be  used  in  the  same  way.  If  careful  watch  is 
kept  for  the  pest  it  can  probably  be  detected  in  time  to  apply 
the  arsenicals,  which  will  be  much  the  easiest  and  most  effective 
to  use,  but  if  not  observed  until  the  canes  arc  fruiting  they  should 
be  sprayed  with  hellebore,  1  ounce  to  1  gallon  of  water.  Helle]:)orc 
may  be  dusted  on  the  plants  mixed  with  twice  its  weight  of 
flour,  but  the  spraying  may  be^  done  more  thoroughly. 

The  Raspberry  Byturus  * 

The  Raspberry  Byturus   is  a  small    brown    beetle  belonging 

to  the  same  family  as  the  larder  and  carpet  beetles,  most  of  which 

feed    on   animal   matter.     It   is    about   one-seventh    inch  long, 

reddish-yellow  or  reddish-brown,  and  covered  with  a  thick  coat 

*  Byturus    unicolor    Say.     Family    Dermestidoe.     See    W.    H.    Goodwin, 
Bulletin  202,  Ohio  Agr.  Exp.  Sta. 


INSECTS  INJtJRIOUS   TO  RASPBERRY  AND  BLACKBERRY      475 


of  pale,  tawny  hairs.  The  beetles  appear  about  the  middle  of 
May  in  northern  Ohio.  They  feed  on  the  tender  foliage  and  eat 
into  the  flower  buds,  and 
sometimes  emerge  in  such 
numbers  that  the  young  foli- 
age is  skeletonized  and  many 
of  the  flower  Ijuds  do  not 
develop.  Though  the  eggs  are 
laid  in  June,  they  have  not 
been  observed.  The  larvie 
appear  in  late  June  and  July 
and  feed  in  the  fleshy  head  on  which  the  berry  is  born,  causing 
the  affected  berries  to  ripen  earlier,  making  them  small  and  unfi  t 
for    market.     Furthermore    the    little    larviB    not     infrequently 


Fig.  341. — Larva  and  adult  of 
the  ra.spberry  bytiu-us — enlarged. 
(After  Goodwin.) 


Fig.  342. — Early  ripening   berries,  the   smaller  ones   infested   with  Byturus 
larva>.     (After  Goodwin.) 

remain  in  the  cup  of  the  berry,  which  necessitates  picking  teh 
berries  over  and   injures  their   sale.     The  larva  is  about   one- 


476        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

quarter  inch  long,  rather  plump  and  cylindrical,  and  tapering 
at  each  end.  The  body  is  white,  but  each  segment  is  marked 
across  the  back  with  a  broad,  tawny  yellow  band,  and  numerous 
short  white  hairs.  When  full  grown  the  larva  drops  to  the 
ground  and  forms  an  earthen  cell  just  beneath  the  surface,  in 
which  it  transforms  to  a  yellowish  pupa,  from  which  the  beetle 
emerges  the  next  spring.  Only  red  raspberries  seem  to  be  affected, 
and  some  varieties  are  particularly  injured.  The  insect  has  been 
reported  as  injurious  from  Minnesota  to  Massachusetts  and  in 
Ontario. 

Control. — Inasmuch  as  the  beetles  feed  freely  on  the  foliage 
before  ovipositing  they  may  be  destroyed  by  spraying  the  leaves 
with  arsenate  of  lead.  Mr.  Goodwin  has  shown  that  where 
foliage  was  sprayed  with  4  pounds  per  barrel,  that  three-fourths 
of  the  subsequent  injury  to  the  berries  by  the  larvse  was  prevented 
by  the  destruction  of  the  beetles,  and  the  injury  to  the  flower 
buds  was  also  lessened.  Thorough  cultivation  in  the  fall  close 
around  the  bushes  will  probably  destroy  many  of  the  pupae  by 
exposing  them  to  winter  weather. 


CHAPTER  XXIV 

INSECTS   INJURIOUS  TO  THE   CURRANT  AND   GOOSEBERRY 

The  Imported  Currant-borer  * 

One  of  the  worst  pests  of  the  ciyrant  and  gooseberry  is  the 
borer,  which  tunnels  out  the  canes  and  where  abundant  frequently 
kills  the  plants.  It  is  a  European  insect  which  has  spread  to 
all  parts  of  this  country  where  these  fruits  are  grown.  The 
adult  is  one  of  the  clear-winged  moths  and  with  the  larva  is  very 


Fig.  343. — The  imported  currant-borer  (Aegeria  tipuliformis  Clerck):  moth, 
larva,  and  empty  pupal  skin  left  protruding  from  burrow.  (After 
Lugger.) 

similar  in  appearance  and  habits  to  the  raspberry  root-borer 
(p.  459).  The  moth  is  about  one-half  inch  long  with  a  wing- 
expanse  of  three-quarters  inch.  The  body  is  black  with  a  steel- 
blue  lustre,  with  a  bright  yellow  band  around  the  neck  and  three 

*  JEgeria  tipuliformis  Clerck.     Family  Sesiidoe.     See  Lugger,  1st  Report 
Minn.  State  Entomologist,  p.  184. 

477 


478        INSECT  PESTS  OF   FARM,   GARDEN  AND  ORCHARD 

yellow  bands  across  the  abdomen,  which  bears  a  large  tuft  of 
long  scales  at  the  tip.  The  wings  are  clear  except  for  a  margin 
of  blackish  scales  and  a  band  across  the  fore-wings  about  one- 
third  from  the  tip. 

Life  History. — The  moths  appear  in  June  and  deposit  their 
small  globular,  brown  eggs  in  the  axils  of  the  leaves  next  the 
canes,  or  under  scales  or  in  cracks  of  the  canes.  The  3'oung 
caterpillars  bore  into  the  pith  of  the  canes,  which  they  tunnel  out, 
and  are  about  half  grown  by  winter,  when  they  descend  to  the 
bottom  of  the  burrows  and  hibernate.  In  the  spring  they  con- 
tinue their  work  and  become  full  grown  b}"  Ma3\  The  full- 
grown  larva  is  slightly  over  one-half  inch  long,  of  a  yellowish 
color,  with  brown  head,  and  with  numerous  small  tul^ercles  over 
the  body.  It  cuts  a  hole  through  the  side  of  the  burrow,  which 
it  closes  with  small  chippings,  and  then  transforms  to  the  pupa. 
When  the  moth  is  ready  to  emerge  the  pupa  wriggles  itself  partly 
out  of  the  burrow  Ijy  means  of  the  strong  spines  on  the  abdomen, 
and  the  moth  comes  forth.  Affected  canes  can  be  recognized 
by  the  dwarfed  and  yellow  foliage  and  the  general  unhealthy 
appearance  of  the  plant,  and  if  not  removed  will  usually  die  during 
the  season. 

Control. — The  only  methotl  of  control  is  to  keep  all  the  old 
wood  removed  and  to  cut  out  and  burn  all  affected  canes  in  fall 
or  early  spring,  whenever  the  injury  may  best  be  detected. 

The  Currant-stem  Girdler  * 

In  late  spiing,  after  the  young  currant-shoots  have  reached 
a  growth  of  several  inches,  two  or  three  inches  of  the  tips  some- 
times wilt,  and  fall  over  and  hang  suspended  or  drop  to  the  ground. 
If  examination  shows  that  the  tip  has  been  girdled  by  several 
sharp  cuts,  it  is  probably  the  work  of  the  Currant-stem  Girdler. 
It  is  a  native  insect  which  was  first  descril)ed  from  Massachusetts, 
and  has  also  been  found  injurious  in  Rhode  Island,  Canada,  Ohio 

*  Janus  integer  Norton.  Family  Tenthredinidoe.  See  Slingerland,  Bul- 
letin 126,  Cornell  Univ.  Agr.  Exp.  Sta.;  F.  H.  Chittenden,  Bulletin  No.  46, 
Bureau  of  Forestry,  pp.  68-70. 


Fig 


344.— The  currant  stem-girdler  {Janus  integer  Norton):  a,  female  at 
work  girdling  a  currant  stem— natural  size;  b,  girdled  portion  of  stem 
much  enlarged  to  show  character  of  girdle;  c,  stem  cut  open  to  show 
egg;  d,  egg— much  enlarged.     (After  Slingerland.) 


480 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


and  Michigan,  but  has  been  most  troublesome  in  New  York. 
It  has  also  been  noted  as  a  pest  of  willow  and  poplar  in  Mary- 
land, and  of  basket  willow  in  Kentucky,  Indiana,  and  Ohio,  so 
that  it  is  doubtless  quite  generally  distributed.  The  adult  insect 
is  a  slender  saw-fly  with  shining  black  body  and  light  brownish 
legs,  shown  natural  size  in  Fig.  3-i4a.  The  male  is  smaller  and 
has  a  brownish-yellow  abdomen,  while  in  the  female  the  first 
half  of  the  abdomen  is  reddish-orange  and  the  rest  is  black.  The 
adults  are  abroad  in  May,  l3ut  are  very  shy  and  are  seldom  seen. 


Fig.  345. — Currant  stem  girdled  by  the  stem-girdler.     (After  Slingerland.) 

They  are  saw-flies  in  the  truest  sense  of  that  term,  for  the  female 
makes  most  effective  use  of  her  saw-like  ovipositor,  as  has  been 
very  interestingly  described  and  illustrated  by  Professor  Slinger- 
land. The  ovipositor  is  thrust  into  the  cane  for  its  whole  length,, 
and  through  it  the  egg  is  deposited  in  the  pith.  The  egg  is  an 
elongate-oval  shape,  yellowish-white,  and  about  one-twenty-fifth 
inch  long  (Fig.  344d).  Immediately  the  female  moves  an  inch 
or  two  higher  and  girdles  the  stalk  by  numerou::  thrusts  of  her 
ovipositoi",  which  is  thrust  in  and  then  given  a  twist  to  one  side 
so  that  it  comes  out  at  one  side  of  where  it  was  forced  in,  and 
makes  a  horizontal  cut.     The  eggs  are  laid  in  late  May  and  early 


INSECTS   INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      481 

June  and  hatch  in  about  eleven  days.  The  young  larvae  bore 
into  the  pith,  but  the  tunnel  rarely  extends  over  six  inches  below 
the  point  girdled.  The  full-grown  larva  is  hardly  one-half  inch 
long,  of  a  glistening  sti'aw-yellow  color,  with  darker  head.  The 
thoracic  segments  arc  wider  than  the  others  and  bear  rudimentary 
feet,  and  from  the  tip  of  the  stout,  cylindrical  abdomen  projects 
a  horny,  brown  bifid  spine.  In  the  fall  the  borer  cleans  out  its 
burrow  at  the  lower  end  and  eats  a  hole  through  the  woody  wall 
of  the  stem  to  the  outer  bark,  which  sinks  in  at  this  point.  The 
grub  then  spins  a  thin  silken  cocoon  about  itself,  in  which  it 
hibernates  over  winter,  transforming  to  a  whitish  pupa  in  April, 
from  which  the  adult  emerges  early  in  May.  The  girdling  of 
the  stalks  is  the  principal  injury,  and  those  which  harbor  the  pest 
may  be  recognized,  even  in  winter,  by  the  characteristic  dead 
stubs,  cut  off  squarely  at  the  upper  end. 

Control. — The  drooping  of  the  tips  in  May  is  soon  noticed 
and  during  June  they  should  be  cut  off  about  three  inches  lower 
down  and  burned,  or  if  the  pruning  is  left  until  winter  the  infested 
stubs  should  be  cut  off  about  eight  inches  below  the  point  girdled, 
as  the  larvae  rarely  tunnel  deeper. 

The  Four-lined  Leaf-bug  * 

This  is  one  of  our  most  common  Icaf-l^ugs,  which  has  a  long 
list  of  food  plants,  but  is  particularly  injurious  to  the  young 
foliage  of  currant  and  gooseberry.  The  adult  bug  is  easily 
recognized,  as  the  upper  surface  is  a  dark  green  with  four  stripes 
and  the  tips  of  the  wing-covers  black,  as  shown  in  Fig.  346.  The 
green  changes  to  yellow  after  death  and  the  body  is  bright  orange- 
yellow,  and  the  legs  green.  The  "  presence  of  the  pest  is  indicated 
by  the  appearance  of  the  peculiar  brown  depressed  spots  on  the 
tender  terminal  leaves  "  in  early  summer.  ''  As  the  attack  con- 
tinues, whole  leaves  turn  brown,  curl  up,  become  brittle,  and  are 
torn  or  broken  by  the  wind.  The  young  shoot  is  checked  and 
frequent^  droops  and  dies.     The  buds  of  dahlias  and  roses  are 

*  Poecilocapsus  lineatus  Fab.  Family  Capsidoe.  See  Slingerland,  Bul- 
etin  58,  Cornell  Univ.  Agr.  Exp.  Sta. 


482        INSECT  PESTS  OF  FARM,  GARDEN  AND   ORCHARD 


often  blasted."  Slingerland  gives  a  list  of  some  fifty-seven  food- 
plants,  including  all  sorts  of  crops,  ornamental  plants  and  weeds. 
Parsnip,  mint,  sage,  rose,  dcutzia,  dahlia,  and  others  are  often 
badly  injured.  The  species  has  been  observed  fi-om  Canada  to 
Geoi-gia  and  westward  to  the  Dakotas,  so  that  it  is  pro])al)ly 
generall)^  distributed  east  of  the  Rockies. 

Life  History. — The  nymphs  hatch  from  the  overwintering  eggs 
in  late  May  and  early  June  and  are  very  largely  responsible 
for  the  injury  to  the  foliage.     The  newly  hatched  nymph  is  only 


a  b 

Fig.  346. — The  four-lined  leaf-bug  {Poecilocapsus  lineatus  Fab.):  a,  adult; 
b,  cross-.section  of  stem  showing  eggs  in  po.sition  and  a  single  egg  greatly 
enlarged.     (After  Slingerland.) 

about  one-twentieth  inch  long,  but  is  easily  recognized  by  the 
shining  vermilion-red  color  of  the  body,  marked  with  large  blackish 
spots  on  the  thorax  and  with  greenish-black  antennae  and  legs. 
The  nymphs  grow  rapidly,  becoming  full  grown  in  seventeen  to 
twenty  days  after  hatching,  during  which  time  they  have  molted 
five  times.  The  full-grown  nymph  is  about  one-fifth  inch  long, 
bright  orange  yellow,  and  the  lalack  wing-pads  extend  half  way 
to  the  end  of  the  abdomen  and  bear  a  3'ellowish  green  stripe  near 
the  outer  margin.  The  nymphs  feed  on  the  tenderest  young 
leaves,  sucking  out  the  juices  and  soft  tissue  through  their  tiny 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      483 


beaks,  and  thus  causing  the  spots  mentioned.  "■  As  the  nymphs 
increase  in  size  the  spots  are  a  little  larger  and  more  numerous, 
initil  not  only  hundretls  occur  on  a  single  leaf,  but  often  nearly 
all  the  parenchyma  is  taken  from' the  leaf."  The  nymphs  are 
very  active  and  dart  from  one  side  of  the  leaf  to  the  other  when 
disturbed.  The  adult  bugs  appear  about  the  middle  of  June 
and  are  active  for  a  month  or  more,  when  they  disappear.  They 
mate  and  the  females  commence  to  lay  eggs  about  a  week  after 


Fig.  347. — Currant  leaf  spotted  by  the  nymphs  of  the  four-Hned  leaf-bug. 

(After  Shngerland.) 

they  first  appear.  The  female  is  furnished  with  a  strong  ovipositor 
with  which  she  inserts  the  eggs  in  slits  cut  lengthwise  into  the 
stems  of  the  plants  extending  nearly  half  way  through  the  pith. 
A  half-dozen  or  more  eggs  are  packed  together  in  the  small  slit, 
which  may  be  one-eighth  inch  long.  The  individual  egg  is  about 
one-sixteenth  inch  long,  light  yellow,  and  shaped  as  in  Fig.  346e, 
with  the  upper  third  capped  by  a  white,  finely  striated  portion. 
''  With  the  growth  of  the  surrounding  tissue  of  the  stem,  the  eggs 


484        INSECT  PESTS    OF  FARM,    GARDEN  AND  ORCHARD 

are  usually  forced  out  of  the  slit  somewhat,  so  that  about  one-half 
...  of  the  white  portion  of  the  egg  projects  from  the  slit." 
Most  of  the  slits  are  made  two  or  three  inches,  rarely  over  six 
inches,  below  the  tender  tips. 

Control. — Experiments  indicate  that  the  nymphs  may  be 
killed  by  spraying  them  with  kerosene  emulsion  containing  10 
per  cent  kerosene.     Tobacco  extracts  should  also  be  tried.     The 


Fig.  348. — Currant  leaves  killed  by  the  four-lined  leaf-bug.     (After  Slinger- 

land.) 

adults  are  not  susceptible  to  this  treatment,  however.  Both 
nymphs  and  adults  will  drop  from  the  foliage  when  disturbed, 
and  Professor  Slingerland  has  suggested  that  they  might  be  jarred 
into  a  pan  of  kerosene.  By  drawing  pans,  such  as  constructed 
for  combating  the  pea-aphis  (p.  326),  between  the  rows  and 
jarring  the  ])ugs  into  them,  many  might  be  destroyed.  As  the 
eggs  are  readily  recognized,  the  tips  containing  them  should  be 
cut  off  and  destroyed  during  the  winter. 


The  Currant-aphis  * 

The  young  foliage  of  currants,  and  sometimes  of  gooseber- 
ries, is  often  found  curled  up  in  late  spring  with  many  bladder- 

*  Myzus  ribis  Linn.  P'amily  Aphididoe.  See  V.  H.  Lowe,  Bulletin  139, 
N.  Y.  Agr.  Exp.  Sta.,  p.  660.  Another  species,  Rhopalosiphum  ribis  Linn., 
is  also  common  on  currant  and  is  described  and  figured  by  Mr.  Lowe. 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY       485 

like  galls  on  the  leaves,  inside  of  which  are  found  the  numerous 
yellowish-green  plant-lice  which  liavo  caused  them.  The  wing- 
less females  are  about  one-twelfth  inch  long,  yellowish-green 
or  green,  mottled  with  darker  shades,  and  with  bright  red  eyes. 
The  winged  female  is  slighth'  longer,  with  wings  expanding  one- 
third  inch.  It  is  bright  greenish-yellow,  with  pale  olive  head, 
thoracic  lobes  brown,  and  the  abdomen  is  marked  by  several  dark 
transverse    bands    and    lateral    spots.     It    is    an    old    European 


Fw.  349. — Currant  foliage  curleti  by  aphides.     (After  Lowe.) 

species  and  is  probabl}'  found  throughout  the  United  States  where 
currants  are  grown. 

Life  History. — The  life  history  is  practically  the  same  as  that 
of  several  other  aphides  previously  described  and  need  not  be 
rehearsed  in  detail.  The  small  black  eggs  are  found  on  the  stalks 
in  winter  and  hatch  just  as  the  foliage  appears.  The  aphides 
multiply  on  the  foliage,  causing  it  to  curl  as  described,  until 
midsummer,  when  they  either  migrate  to  some  other  food-plant 
or  become  greatly  reduced  in  numbers  through  the  attacks  of 
parasites  and  predaceous  insects,  which  are  very  effective  in  the 
control  of  this  species.  Mr.  Lowe  states  that  a  few  females  may 
be  found  on  the  foliage  throughout  the  summer.     In  late  October 


486 


INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


winged  males  appear  and  mate  with  the  true  females,  w^hich  then 
lay  the  eggs. 

Control. — The  aphides  may  be  readily  killed  by  spraj-ing  wdth 
kerosene  emulsion,  whale-oil  soap,  1  pound  to  6  gallons  of  water, 
or  tobacco  extracts,  but  the  spraying  must  be  done  before  the 
foliage  becomes  badly  curled.  Ordinarily  they  may  be  held 
in  check  by  picking  off  the  curled  leaves  by  hand. 


The  Imported  Currant- worm  * 

^'  The  most  destructive  insect  that  attacks  the  currant,"  says 
Professor    Lugger,    "  is    the    above-named    saw-fly,   which  feeds 


Fig.  350. — The  imported  currant-worm  {Pteronus  ribesii  Scop.):  a,  male  and 
female  saw-flies;  b,  larva?;  c,  pupa;  d,  cocoon;  e,  eggs — all  enlarged. 
(After  Lugger.) 

indiscriminately  on  all  kinds  of  currants  and  gooseberries.     The 
imported  species  is  supposed  to  have  been  accidentally  introduced 

*  Pteronus  ribesii  Scop.  Family  Tenth  red  inid<iE.  Sec  Lugger,  Bulletin 
43,  Minn.  Agr.  Exp.  Sta.,  p.  179;  C.  L.  Marlatt,  Bulletin  3,  Tech.  Series, 
Div.  Ent.,  p.  61. 


INSECTS  INJURIOUS  TO  CURRANT  AND   GOOSEBERRY       487 

into  this  country  about  the  year  1S57,  and  has  since  spread  over 
the  greater  part  of  the  United  States  and  Canachi.  The  eggs  are 
gkied  to  the  main-ril)s  of  the  leaf  as  shown  in  Fig.  350,  and  not 
inserted  into  pockets,  as  is  usually  the  case  with  saw-flies.  .  .  . 
In  from  four  to  ten  days  the  egg  hatches  into  a  very  small  whitish 
caterpillar  with  a  white  head  and  ornamented  with  black  spots 
on  each  side.  This  color,  however,  changes  to  green  as  soon  as 
the  caterpillars  begin  to  feed,  and  after  their  first  skin  is  shed, 
the  hiiiid  becomes  black  and  many  black  spots  appear  on  the  body. 
This  coloration  persists  until  the  last  molt  when  the  insect  becomes 
grass-green.  The  head,  however,  retains  the  l^lack  spots  on 
each  side.  The  length  of  the  worm  is  now  about  three-fourths 
of  an  inch.  While  growing  they  at  first  skeletonize  the  leaves; 
later  they  eat  the  entire  leaf,  with  the  exception  of  the  ribs,  and  at 
last  they  devour  immense  quantities  of  them,  often  completely 
stripping  the  bushes  of  their  foliage.  If  this  is  repeated  year  after 
year,  the  plants  produce  less  and  less  fruit  and  eventually  die. 
The  larvae  now  descend  to  the  ground,  in  which  they  spin  a  small, 
oval  cocoon  of  Ijrownish  silk,  either  just  l)elow  the  surface  of 
the  ground  or  among  the  leaves  and  rubbish  that  collect  Ijclow  the 
plants.  Inside  these  cocoons  they  change  to  pupa;  and  later 
to  adults,  which  are.  ready  to  issue  as  winged  saw-flies  during  the 
last  of  June  or  in  July  (in  Minnesota),  sometimes  not  until  the 
^rst  of  August.  They  now  pair  and  produce  a  new  generation 
of  injurious  w'orms  .  .  .,  the  adults  of  which  do  not,  however, 
issue  until  the  following  spring.  As  the  two  l)roods  overlap, 
we  can  find  larvae  of  all  stages  during  the  greater  part  of  the 
summer."  The  adult  saw-flies  are  well  illustrated  in  Fig.  350. 
The  female  is  about  one-third  inch  long,  of  a  light  yellowish  color 
marked  with  blackish  as  shown  in  the  figure,  while  the  male  is 
smaller  and  rather  darker. 
Control. — See  page  -488. 

The  Native  Currant-worm  * 

The  native  currant-worm  is  not  usually  so  destructive  as  the 
European   species,    but   occasionally   becomes   injurious    and    is 

*  Gymnonychus  appendiculatus  Hartig.     Family  Tenthredinidoe. 


488        INSECT   PESTS  OP  FARM,  GARDEN  AND  ORCHARD 

widely  distributed,  occurring  from  New  England  to  Minnesota 
and  Colorado,  in  British  Columbia,  and  probably  in  the 
Pacific  States.  The  larva  is  about  two-thirds  the  size  of  the 
imported  species,  but  is  uniformly  pale-green  except  the  head 
which  is  black  until  the  last  molt,  after  which  it  becomes  partly 
green.  One  generation  of  larvae  appears  in  late  June  and  another 
in  August.  The  cocoons  are  usually  attached  to  the  twigs  or 
leaves  of  the  bushes.  The  female  saw-fly  is  dull  black  with  dull 
yellow  head,  and  honey-yellow  legs. 

Control. — While  fruiting  the  foliage  should  be  dusted  or  sprayed 
with  hellebore,  which  is  the  time-honored  remedy  for  currant- 
worms  (p.  47).  However,  before  the  fruit  has  set  and  after  it 
is  picked,  spraying  with  arsenicals  will  be  much  cheaper  and  more 
effective,  and  as  it  is  often  desirable  to  spray  gooseberries  for 
diseases  with  Bordeaux  mixture,  by  adding  arsenate  of  lead  or 
Paris  green  to  it,  the  worms  may  be  easily  controlled. 


The  Currant  Span-worm* 

The  Currant  Span-worm  is  readily  distinguished  from  the  other 
currant  "  worms,"  by  being  one  of  the  measuring-worms  or  inch- 
worms  which  loop  along  as  shown  in  Fig.  351.  It  is  not  frequently 
very  destructive,  but  occasionally  becomes  a  pest,  more  par- 
ticularly of  black  currants  and  gooseberries,  throughout  the 
eastern  half  of  the  country.  The  caterpillar  is  slightly  over  an 
inch  long  when  full  grown,  and  of  a  whitish  color  with  a  wide 
yellow  stripe  down  the  back,  another  along  each  side,  and  several 
black  spots  on  each  segment.  The  under  side  is  white  with  a 
slight  pinkish  tinge,  with  a  broad  yellow  median  stripe,  and  is  also 
spotted  with  black.  The  moth  has  a  wing  expanse  of  about  l\ 
inches,  is  a  pale  yellowish  color,  with  several  brownish  spots, 
varying  in  size  and  sometimes  forming  one  or  two  irregular  bands 
across  the  wings. 

Ldfe  History. — ^The  eggs  (Fig.  351a)  are  laid  in  midsummer  on 

*  Cymatophora  ribearia  Fitch.     Family  Geometridoe. 


INSECTS   INJURIOUS  TO  CURRANT  AND  GOOSEBERRY      489 

the  twigs  of  the  infested  plants  and  hatch  as  the  bushes  come 
into  full  leaf  the  next  spring.  The  caterpillars  become  full 
grown  in  three  or  four  weeks,  when  they  pupate  just  beneath 
the  surface  of  the  soil,  and  two  or  three  weeks  later  the 
moths  emerge. 

Control. — Hellebore  is  not  as  effective  as  against  the  saw-fly 
larvie  and  as  the  larvae  usually  appear  before  the  fruit  is  setting, 
they  may  be  better  controlled  by  spraying  with  arsenicals.     When 


Fig.  351. — The  currant  span-worm  {Cijmalomorpha  riberia  P^itch):  1,  2,  larvae; 
3,  pupa;  a,  egg;  b,  eggs  on  twig;  c,  moth — a,  much  enlarged,  others 
natural  size.     (After  Saunders.) 


the  caterpillars  are  disturbed  they  drop  from  the  foliage,  letting 
themselves  down  by  a  silken  thread  and  remaining  suspended  in 
mid-air  until  danger  is  over,  when  they  reascend  the  thread. 
This  habit  may  be  utilized  for  their  destruction  by  jarring  the 
bush  so  that  they  will  drop,  and  then  passing  a  forked  stick  around 
it  so  that  all  the  threads  may  be  caught  and  the  caterpillars  may 
be  drawn  out  in  groups  and  crushed  with  the  foot. 


490        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Currant-fly  * 

Currants  and  gooseberries  sometimes  turn  red  and  dro])  pre- 
maturely, due  to  the  injury  of  small  maggots  which  may  be  found 
within  them.  The  insect  has  been  troublesome  in  Maine  and  is 
sometimes  a  serious  pest  in  Colorado.  It  is  a  native  insect  and  is 
probably  generally  distributed 'throughout  the  northern  United 
States  and  southern  Canada.  The  adult  fly  is  about  the  size  of 
a  house-fly,  a  pale  yellowish  or  yellowish-brown  color,  with  dark 


Fig.   352. — The   currant-fly    {Epochra  canadensis     Loew.) — much  enlarged. 

(After  Gillette.) 

bands  across  the  wings,  and  a  tapering  abdomen,  as  shown  in 
Fig.  352. 

Life  History. — The  flies  appear  in  late  spring  and  the  females 
deposit  their  eggs  in  the  older  berries.  A  female  will  lay  about 
200  eggs  during  the  period  of  a  month,  placing  but  one  in  a  berry, 
so  that  a  single  fly  may  do  considerable  damage.  The  white  egg 
is  about  one-twenty-fifth  inch  long  and  laid  just  under  the  skin, 

*  Epochra  canadensis  Loew.  Family  Trypetidoe.  See  F.  L.  Harvey, 
Bulletin  35,  Maine  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  CURRANT  AND  GOOSEBERRY       491 

where  it  is  easily  seen.  The  egg  hatches  in  a  few  days  into  a 
small  white  maggot,  which  burrows  around  the  berry  and  then 
feeds  upon  the  seeds.  The  location  of  the  larva  may  be  seen,  as 
the  infested  currant  soon  shows  a  clouded  appearance  and  finall}' 
turns  red  and  a  black  spot  appears.  The  maggot  liecomes  full 
grown  in  about  three  weeks  and  then  eats  its  way  out  of  the  l)erry, 
which  has  usuall}'  fallen  to  the  ground.  The  matur(>  maggot 
enters  the  soil  for  al^out  an  inch  and  there  changes  to  the  pupa, 
from  which  the  fly  emerges  the  next  spring. 

Control.— Xs  the  maggots  usiuill}'  remain  in  the  b(>rri(\s  a  few 
days  after  they  drop,  all  fallen  berries  should  be  frequenth' 
picked  up  and  destroj^ed.  Poultry  running  among  the  bushes 
will  do  this  very  effectually.  Other  methods  will  suggest  them- 
selves from  the  above  life  history,  but  none  seems  to  have  been 
carefullv  tested. 


CHAPTER  XXV 

INSECTS  INJURIOUS  TO  THE  GRAPE  * 

The  Grapevine  Phylloxera  f 

This  insect  is  native  east  of  the  Rocky  Mountains,  where  it 
has  always  lived  upon  wild  vines  and  did  not  attract  attention 
until  it  was  imported  into  France  about  1859,  as  it  does  practically 
no  damage  to  the  native  American  grapes.  It  soon  spread  through 
the  principal  wine  districts  of  southern  Europe,  where  it  caused 


Fig.  353. — The  grapevine  phylloxera  {Phylloxera  vastatrix  Planchon) :  a,  true 
sexual  female,  the  dark  colored  area  indicating  the  single  egg;  b,  egg; 
c,  shrivelled  female  after  oviposition;  d,  foot  of  same;  e,  rudimentary  and 
functionless  mouth-parts.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

immense  losses  and  the  temporary  abandonment  of  vineyards, 
due  to  the  fact  that  the  European  varieties  are  very  susceptible 
and  readily  succumb  to  injury  by  it.  It  has  spread  to  southern 
Russia  and  the  adjoining  countries  of  Asia  and  Algeria,  and  has 
been  carried  to  New  Zealand  and  South  Africa.     In  this  country 

*  See  A.  L.  Quaintance,  Farmers'  Bulletin  284,  U.  S.  Dept.  Agr.;  H.  J. 
Quayle,  Bulletin  192,  Cal.  Agr.  Exp.  Sta.;  F.  Z.  Hartzell,  Bulletin  331,  N.  Y. 
Agr.  Exp.  Sta. 

f    Phylloxera  vastatrix  Planchon.     Family  Aphididce.     See  C.  L.  Marlatt 
Farmers'  Bulletin  70,  U.  S.  Dept.  Agr.,  and  Quayle,  1.  c. 

492 


INSECTS  INJURIOUS  TO  THE  GRAPE  493 

it  is  injurious  only  in  California,  where  it  was  imported  on  French 
vines  about  1S74.  It  was  first  noticed  in  Sonoma  County  and 
since  then  has  spread  to  all  the  principal  grape-growing  regions 
north  of  Tehachapi  and  has  probably  destroyed  50,000  acres. 

This  aphid  exists  in  several  forms,  which  injure  both  foliage 
and  roots.  On  the  leaves  irregular  spherical  galls  are  produced, 
and  the  root-inhabiting  form  produces  galls  on  the  roots.  The 
leaf-galls  are  very  common  on  American  grapes,  but  are  no 
indication  of  the  presence  of  the  root  form,  as  the  roots  are  rarely 
injured  where  the  foliage  is  covered  with  leaf-galls.  On  the  other 
hand  the  European  varieties  rarely  exhibit  any  leaf-galls,  but  are 


Fig.  354. — Under  side  of  grape  leaf  showing  galls  caused  by  Pyylloxera. 

(After  Riley.) 

very  susceptible  to  the  root  phylloxera,  which  multiplies  without 
any  external  indication  of  its  presence  until  the  vine  is  seriously 
injured.  The  injury  to  the  vine  is  not  due  so  much  to  the  sap 
taken  from  the  vine  by  the  myriads  of  aphides  which  may  inhabit 
the  roots,  as  to  their  poisonous  effect  on  the  root  tissue  and  its 
subsequent  decay.  Wherever  the  phylloxera  attack  the  roots, 
small  swellings  are  produced,  composed  of  soft  tissue,  which  soon 
decays.  When  such  a  gall  is  formed  at  the  end  of  a  young  root, 
its  growth  is  stopped,  and  on  larger  roots  a  decay  sets  in  which 
finally  girdles  the  root  and  all  below  the  injured  point  dies.     As 


494        INSECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 

all  the  roots  become  affected  the  vine  stops  growing,  the  leaves 
become  sickly  and  yellowish,  and  the  vine  dies,  and  the  phyl- 
loxera disappears  from  the  rotting  roots,  so  that  the  cause  of  the 
injury  would  be  obscure  were  the  nature  of  the  injury  not  known. 
Life  History. — The  life  history  of  the  phylloxera  is  a  com- 
plicated one,  involving  four  different  forms  of  aphides;  the  leaf- 
gall  form,  the  root  or  destructive  form,  the  winged  or  colonizing 
form,  and  the  sexual  form.  The  winter  eggs  are  deposited  on  the 
rough  bark  of  the  old  wood  in  the  fall  and  hat^'h  the  foUnwine; 


Fig.  355. — The  grapevine  phylloxera:  o,  winged  migrating  female;  h,  last 
stage  of  nymph  of  some;  c,  mouth-parts  with  thread-like  sucking  setae 
removed  from  sheath;  d,  and  e,  eggs  of  male  and  female,  showing  sculp- 
turing— all  enlarged.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

spring.  The  young  aphides  settle  on  the  leaves,  where  the  irrita- 
tion caused  by  their  mouth-parts  soon  causes  a  depression  around 
each  which  forms  a  gall  projecting  on  the  lower  side  of  the  leaf. 
''  In  about  fifteen  days  the  louse  becomes  a  plump  orange-yellow, 
full-grown,  wingless  female,  and  fills  its  gall  with  small  yellow 
eggs,  dying  soon  after.  The  eggs  hatch  in  about  eight  days  into 
young  females  again  like  the  parent,  and  migrate  to  all  parts  of 
the  vine  to  form  new  galls.  Six  or  seven  generations  of  these 
wingless   f(>males   follow   one    another   throughout   the   summer, 


INSECTS  INJURIOUS  TO  THE  GRAPE 


495 


frequently  completely  studding  the  leaves  with  galls."  In 
California  the  young  hatching  from  the  winter  eggs  go  directly 
to  the  roots  where  they  give  rise  to  new  colonies,  there  being  no 
gall  forms,  according  to  Quayl(\  Where  the  leaf-gall  females 
occur  many  of  them  probably  migrate  to  the  roots  during  the 
summer,  and  all  do  so  with  the  approach  of  cold  weather.  In  the 
spring  the  roots  are  attacked  and  a  series  of  generations  of  wingless 
females  multiply  on  them.  As  there  are  five  to  seven  generations 
in  a  season  and  each  female  lays  from  30  (Quayle)  to  100  (Marlatt) 
eggs,  i^  i>  evident  that  the\'  will  soon  be  numerous  enough  to 
destrov  tl\.i  vine.     The  root-inhal)iting  females  are  verv  similar 


Fig.  3.56. — Grapevins  phylloxera:  a,  root  galls;  5,  enlargement  of  same 
showing  disposition  of  lice;  c,  root-gall  louse — much  enlarged.  (After 
:\Iarlatt,  U.  S.  Dept.  Agr.) 

to  those  in  tlii'  leaf-galls,  and  arc  about  one-tWv^n^y-fiftli  inch  long 
when  mature  and  lialf  as  long  when  young  and  active.  They  are 
light  greenish-yellow  in  summer  and  darker  in  winter,  and  when 
numerous  the  infested  roots  look  as  if  dusted  in  spots  with  pow- 
dered mustard,  according  to  Quayle.  He  states  that  "  the  newly 
hatched  insect  is  fairly  active,  and  at  first  moves  trom  place  to 
place  on  the  roots,  but  finally,  when  it  reaches  the  egg-laying 
stage,  inserts  its  sucking-tube  into  the  root  and  remains  fixed." 
During  the  late  summer  and  early  fall  some  of  the  root-lice  develop 
into  winged  females  which  escape  through  cracks  in  the  soil  and 


496        INSECT  PESTS  OF   FARM,    GARDEN  AND  ORCHARD 

fly  to  neighboring  vines.  They  lay  from  two  to  four  eggs  beneath 
the  loose  bark  on  the  old  wood  and  soon  die.  "  The  eggs  are  of 
two  sizes,  the  smaller  and  fewer  in  number  yielding  males  in  nine 
or  ten  days,  and  the  larger  the  females  of  the  only  sexed  generation 
in  the  whole  life  round  of  the  insect.  In  this  last  and  sexed 
stage  the  mouth-parts  of  both  sexes  are  rudimentary,  and  no 
food  at  all  is  taken.  The  insect  is  very  minute  and  resembles  the 
newly  hatched  louse  of  either  the  gall  or  root  form.  After  fertili- 
zation the  single  egg  of  the  larva-like  female  rapidly  increases 
in  size  until  it  fills  the  entire  body  of  the  mother  and  is  laid  within 
three  or  four  days,  bringing  us  back  to  the  starting  point."*  The 
phylloxera  has  been  distributed  over  the  world  by  infested  rooted 
plants  or  cuttings  bearing  winter  eggs,  and  is  spread  locally  by 
means  of  the  winged  females,  by  the  escape  of  the  young  root- 
lice  through  cracks  of  the  soil  and  their  migration  to  neighboring 
plants,  or  l)y  bits  of  infested  roots  being  spread  in  cultivation, 
and  by  the  leaf-gall  lice  being  spread  to  other  plants  by  the  wind 
or  by  being  carried  by  birds  or  insects. 

Control. — The  principal  means  of  control  lies  in  the  use  of 
resistant  vines.  These  may  be  varieties  which  have  proven 
successful  in  the  eastern  United  States,  where  the  insect  is  native, 
or  more  commonly  the  stocks  of  grapes  from  the  Eastern  States 
are  grafted  with  the  desired  varieties.  There  is  a  marked  varia- 
tion in  the  resistance  of  different  species  and  varieties  and  not  all 
of  them  can  be  successfully  used  as  stocks  for  the  desired  scions, 
so  that  the  successful  use  of  the  method,  which  is  fully  outlined 
by  Quayle,  I.e.,  requires  a  considerable  knowledge  of  viticulture. 

Carbon  bisulfide  has  been  used  very  extensively  for  destroying 
the  root-lice,  but  is  expensive  and  is  only  applicable  on  rich,  deep, 
loose  soils.  It  cannot  be  used  successfully  on  soils  containing 
much  clay,  or  on  dry  rocky  hillsides,  or  when  the  soil  is  saturated 
with  moisture,  and  is  most  effective  on  sandy  soils  where  the 
insect  is  least  injurious.  It  is  applied  at  the  rate  of  125  to  250 
pounds  per  acre  at  a  cost  of  $15  to  $25  per  acre.  It  may  be 
applied  any  time  except  during  the  blossoming  and  ripening  of 
*  Quotations  from  Marlatt,  1.  c. 


INSECTS  INJURIOUS  TO   THE  GRAPE  497 

the  fruit,  two  applications,  one  after  vintage  and  the  other  just 
before  blossoming,  giving  the  best  results.  It  is  applied  by 
pouring  one-half  to  three-quarters  ounce  into  holes  a  foot  deep, 
from  IS  to  2-1  inches  apart,  all  over  the  vineyard,  but  not  nearer 
than  one  foot  to  the  vine.  The  holes  may  Ije  niadc^  with  an  iron 
rod  or  dibble  and  are  closed  by  packing  the  soil  down  with  the 
foot  as  soon  as  the  liquid  is  poured  in.  Where  extensively  used 
special  injectors  are  used.  Where  the  vines  are  much  weakened 
they  do  not  withstand  the  effect  of  the  bisulfid(\,  and  treated 
vines  must  be  thoroughly  fertilized  and  cultivated. 

One  of  the  best  methods  of  destroying  the  root-lice  where 
water  is  available  is  by  submersion.  In  California  the  best  results 
are  secured  by  flooding  with  at  least  six  inches  of  water  for  a 
week  or  ten  days  as  soon  as  the  vines  have  ceased  active  growth 
in  November.  A  little  later  two  to  three  weeks'  submersion  will 
be  necessary  and  in  winter  thirty-five  to  forty  days.  Flooding 
for  a  couple  of  days  in  midsummer  seems  to  destroy  some  of  the 
insects,  but  its  main  value  is  in  stimulating  a  vigorous  growth 
of  new  rootlets.  Longer  flooding  in  summer,  when  the  aphides 
might  be  most  easily  destroyed,  injures  the  vines. 

On  very  sandy  soils  vines  are  uninjured  by  the  phylloxera.  All 
sandy  soils  are  unfavorable  to  the  pest  and  vines  on  them  die 
more  slowly,  but  to  secure  complete  immunity  there  must  be  at 
least  60  per  cent  of  siliceous  sand.  Sands  containing  clay  or 
which  form  lumps  offer  less  resistance. 

The  Grapevine  Root-borer  * 

The  larvae  of  the  Grapevine  Root-borer  feed  in  the  old  roots  at 
some  little  distance  from  the  base  of  the  vine,  and  as  there  are 
no  indications  of  the  pest,  its  presence  may  easily  pass  unnoticed. 
Although  not  generally  recognized  as  a  serious  one  it  has  been 
known  as  a  pest  of  the  grape  for  fifty  years,  and  has  been  observed 
to   do    considerable   damage   in    Kentucky   and   West   ^^irginia. 

*  Memythrus  polistiformis  Harris.  Family  Sesiidcp.  See  Fred  E.  Brooks, 
Bulletin  110,  W.  Va.  Agr.  Exp.  Sta. 


498      INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 

Although  the  vines  arc  not  killed,  they  are  so  enfeebled  that  they 
make  but  little  growth  and  the  crop  is  much  curtailed.  All 
varieties  are  affected  in  West  Virginia,  including  the  wild  fox 
grape,  Vitis  labrusca.  It  is  stated  that  in  the  South  the  Scupper- 
nong,  or  southern  wild  fox  grape,  is  immune  from  attack.     The 


Fig.  357. — The  grapevine  root-borer  (Memythrtis  polistiformis  Harris):  male 
and  female  moths  on  wild  lettuce  leaf  under  grapevine — natural  size. 
(From  Brooks.) 

species  has  been  observed  from  Minnesota  and  Missouri,  eastward 
through  Ohio  and  Kentucky  to  West  Virginia  and  North  Carolina. 
The  parents  of  the  borers  are  clear- winged  moths  nearly 
related  to  the  peach-tree  borer,  currant-borer,  and  raspberry- 
borer.  The  females  are  seven-eighths  inch  long  with  wings  expand- 
ing H  inches.     Thev  are  a  dark  lustrous  brown  color,  tho  fore- 


INSECTS  INJURIOUS  TO  THE  GRAPE  499 

wings  being  brown  and  the  hintl-wings  transparent  and  ])ordered 
with  brown.  Tlie  posterior  margins  of  tlie  second  and  fourth 
abdominal  segments  are  orange  or  lemon-yellow,  and  there  are 
spots  of  the  same  color  at  the  bases  of  the  wings.  The  males 
are  considerably  smaller  than  the  females.  The  moths  fly  during 
the  day  and  arc  readil}'  mistaken  for  wasps  of  the  genus  Polistes. 
The  males  fly  in  a  quick,  wasp-like  manner,  and  when  they  rest 
on  a  leaf  will  occasionally  flutter  the  wings  like  an  angry  wasp, 
which  is  accompanied  by  a  low  buzzing  sound,  which  makes  the 
mimicry  very  effective. 

Life  Histori/. — The  eggs  are  laid  singly  on  weeds,  grasses  or 
other  vegetation  in  the  vineyard  or  on  the  bark  or  leaves  of  the 
vines,  a  single  female  laying  some  400  eggs. 
The  egg  is  oval,  one-twenty-fifth  inch  long. 
of  chocolate-l:)rown  color,  and  finely  pitted 
and  sculptured.  They  are  very  readily  washed 
off  by  the  rain  and  drop  to  the  soil,  where 
they  hatch  in  al)out  three  weeks.  The  little 
larvae   bore    directly    into    the    soil,  wherever 

they  may  be,  in  search   of  grape  roots,  and       j.-i,;  35s. Egg  of 

may   survive    for   several    days    without    any         grapevine  root- 
food.     Upon  reaching  a  root  the  larva  bores  ^,        ,        r 
^                        °                                                                gi'eatly  enlarged. 

through  the  outer  bark  and  then  makes  an  (After  Brooks.) 
irregular  burrow  in  the  softer  parts  of  the 
bark,  which  may  encircle  the  root  several  times.  As  the  bur- 
rows grow  larger  they  run  with  the  grain  of  the  wood,  and  as 
they  are  enlarged  with  the  growth  of  the  larva,  only  the  outer 
bark  is  left  on  roots  of  one-half  inch  or  less  in  diameter,  the  interior 
being  tunnelled  out  and  filled  with  the  castings  of  the  larva.  Most 
of  the  larv:B  feed  a  foot  or  so  from  the  base  of  the  vine,  though  one 
was  found  on  a  root  nine  feet  from  the  base.  The  larvte  bore  in  the 
roots  until  the  second  fall,  when  they  are  about  full  grown  and 
make  cells  or  hibernacula,  thinly  lined  with  silk,  in  which  they 
hibernate  in  the  root.  The  larva  becomes  full  grown  the  next 
spring  and  is  then  1^  to  If  inches  long,  of  the  general  shape 
shown  in  Fig.  359,  yellowish-white,  with  a  small  brown  head,  three 


500 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


pairs  of  brown  thoracic  legs,  and  five  pairs  of  abdominal  prolegs. 
When  ready  to  pupate  the  larva  comes  near  the  surface  of  the 
soil  and  there  makes  a  tough  cocoon  an  inch  or  so  long,  composed 
of  earth  and  excrement  and  lined  with  silk,  and  in  it  ti-ansfo|-ms 


Fio.  359. — Grapevine  root-borers  at  work.     Five  borers  were  feeding  in  this 
.  section  when  taken  from  the  ground — two-thirds  natural  size.     (Photo 
by  W.  E.  Rumsey.) 

to  a  brown  pupa  with  j^ellow  bands  around  the  abdomen.  In 
about  four  or  five  weeks  the  pupa  wriggles  half  way  out  of  the 
cocoon  and  the  moth  emerges,  leaving  the  empty  pupal  skin 
projecting  above  the  surface  of  the  ground.     The  moths  emerge 


INSECTS  INJURIOUS  TO  THE   GRAPE  501 

in  late  July  and  early  .\ugust  in  West  Virginia  and  the  eggs  are 
laid  in  a  few  days.  Thus  the  life  cycle  requires  two  full  years 
and  larvae  of  two  sizes  may  be  found  in  the  roots  at  any  time, 
except  during  the  pupal  period,  when  all  will  be  about  half  to 
two-thirds  grown. 

Control. — On  account  of  their  subterranean  habits  it  is  mani- 
fcsth'  impossil:)le  to  dig  out  the  borers,  as  is  done  with  similar 
species  except  for  a  few  valuable  vines.  If  the  Scuppernong  is 
as  immune  as  has  been  reported,  it  might  be  used  as  a  stock 
throughout  the  South,  where  it  will  thrive.  By  recognizing  the 
parent  moths,  they  may  be  destroyed  by  approaching  them  quietly 
when  at  rest  and  striking  them  quickly  with  a  paddle  or  board  and 
many  might  thus  be  killed  during  the  time  they  arc  most  abundant. 
By  thorough  cultivation  in  June  and  July  many  of  the  cocoons 
will  be  thrown  to  the  surface  or  buried  so  deeply  that  many  of 
the  pupse  will  be  destroyed,  or  the  adults  will  be  unable  to  reach 
the  surface.  With  liberal  fertilization,  cultivation  will  stimu- 
late the  vine  to  withstand  the  injury.  Brooks  has  shown  that 
in  West  Virginia  the  crested  flycatcher  (Myiarchus  crinitus) 
feeds  upon  the  moths  and  may  be  a  factor  in  the  control  of  the 
pest. 

The  Grape  Root-worm  * 

The  Grape  Root-worm  is  the  larva  of  a  small,  hairy,  chestnut- 
brown  beetle  which  feeds  on  the  upper  surfaces  of  the  leaves, 
eating  out  series  of  patches  or  holes  in  characteristic  chain-like 
feeding  marks  which  afford  an  easily  recognizable  indication  of  the 
presence  of  the  pest  in  the  vineyard.  The  larvae  devour  the  smaller 
roots  and  eat  out  pits  and  burrows  in  the  larger  roots,  and  where 
abundant  may  kill  the  plants  in  a  year  or  two,  but  more  commonly 
they  cause  an  enfeebled  growth  and  a  consequent  failure  to  pro- 
duce profitable  crops.  Injury  has  been  most  severe  in  the  grape  belt 

*  Fidia  viticida  Walsh.  Family  Chrysomelidce .  See  Quaintance,  I.e.; 
Hartzell,  I.e.;  M.  V.  Slingerland,  Bulletins  184,  208,  224,  and  23.5,  Cornell 
Univ.  Agr.  Exp.  Sta.;  E.  P.  Felt,  Bulletin  19,  Office  State  Ent.  of  N.  Y.; 
Fred  Johnson,  Bulletin  68,  Part  VI,  Bureau  Entomology,  U.  S.  Dept.  Agr.; 
Johnson  and  Hammar,  Bulletin  89,  ibid. 


502         INSECT  PESTS   OF  FARM,  GARDEN  AND  ORCHARD 


Fig.    360. — Grape   root-worm    {Fidia   vilicola   Walsh):     beetles   feeding 
foliage — natural  size,  and  enlarged.     (After  Slingerland.) 


INSECTS  INJURIOUS  TO  THE  GRAPE 


503 


of  western  New  York,  Pennsyhania,  and  northern  Ohio,  but  the 
species  occurs  generally  throughout  the  Mississippi  \'alley  and 
the  Eastern  States,  and  has  been  reported  from  CaKfornia.  ''  The 
insect  thrives  best  in  vineyards  which  are  neglected,  and  in  the 
absence  of  cultivation  and  timely  spraying  it  is  likely  to  become 


Fig.  361. — The  life  cycle  of  the  grape  root-worm — enlarged  and  natural  size- 
(After  Slingerland.) 

a  serious  pest  in  any  vineyard  throughout  its  range  of  distribu- 
tion. This  is  especialh'  the  case  in  light,  sandy  soils  and  in  regions 
where  grape  growing  is  a  considerable  industry."  A  nearly 
related  species,*  has  been  known  to  seriously  injure  the  foliage 
in  Texas,  but  it  is  not  known  whether  it  affects  the  roots.     In 

*  Fidia  cana. 


504        INSECT  PESTS  OF  FARM,   GARDEN   AND  ORCHARD 


California,  the  imported  grape  root-worm  *  is  sometimes  destruc- 
tive, has  practically  identical  habits,  and  is  controlled  by  the 
same  methods. 

The  adult  beetle  is  about  one-quarter  inch  long,  brownish  in 
color,  and  covered  with  grayish-white  hairs,  with  a  stout  body 
and  long  legs,  as  shown  in  Fig.  360.    The  full-grown  larva  is  about 


Fig.  362. — Eggs  of  the  grape  root-worm,  natural  size  as  seen  on  grape  canes 
above — enlarged  below.     (After  Slingerland.) 

five-eighths  inch  long,  whitish  in  color,  and  usually  rests  in  a  curved 
position  as  shown  in  Fig.  361.  The  head  is  slightly  narrower  than 
the  body  and  yellowish-brown,  as  are  the  well-marked  spiracles 
on  the  side  of  each  segment. 

*  Adoxus  vitis  Fourcroy.     A  small  shining  brown  or  black  beetle,  on&> 
fifth  inch  long.     See  Quayle,  1.  c. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


505 


Life  History. — The  adult  beetles  appear  about  the  close  of  the 
blooming  period,  or  in  late  June  and  early  July  in  the  latitude 
of  New  York,  and  live  for  a  month  or  more.  They  emerge  earlier 
on  warm,  light  sandy  soils,  and  later  on  heavier  soils.  In  a  few 
days  their  feeding  commences  to  be  noticed  on  the  leaves  and  the 
females  may  be  found  laying  their  eggs.  A  female  will  lay  from 
150  to  900  eggs,  averaging  about  175,  most  of  which  are  laid 


Fig.  363. — Portions  of  three  grape  roots  denuded  of  their  bark  and  fibrous 
roots  by  grape  root-worms,  and  part  of  a  similar  root  taken  from  a  thrifty 
vine  showing  its  normal  bark  and  rootlets.  Reduced  in  size.  (After 
Slingerland.) 

during  the  first  two  or  three  weeks.  The  eggs  are  laid  in  masses 
of  25  to  40  beneath  the  old  bark  or  generally  over  the  canes. 
The  individual  egg  is  one-twenty-fifth  inch  long,  at  first  whitish, 
but  soon  turns  yellow,  and  tapers  at  each  end.  The  eggs  hatch 
in  from  nine  to  twelve  days,  when  the  young  larvae  drop  to  the 
ground  and  seek  the  roots.  The  young  larvae  are  only  one- 
seventeenth  inch  long,  so  that  they  are  able  to  penetrate  the  soil. 


506       INSECT  PESTS   OF  FARM,   GARDEN  AND  ORCHARD 

When  established  on  the  roots  they  feed  freely  and  grow  rapidly, 
becoming  nearly  full  grown  by  fall.  In  the  fall  they  descend 
several  inches  into  the  soil  and  make  small  earthen  cells,  in  which 
they  hibernate.  In  the  spring  they  return  to  the  roots  nearer 
the  surface,  and  those  not  already  full  grown  feed  until  growth 
is  completed.  They  then  make  small  earthen  cells  2  or  3  inches 
below  the  surface  of  the  ground  in  which  they  transform  to  pupse. 
These  cells  are  easily  broken  open  and  the  pupa)  are  thus  crushed 
or  killed  by  stirring  the  soil  in  cultivation.  The  pupa,  shown 
in  Fig.  364,  e,  is  one-quarter  to  one-third  inch  long,  whitish,  with 


Fig.  364. — The  tender  pupa  of  the  grape  root-worm  in  its  earthen  cell,  enlarged 
natural  size  at  n.     (After  Slingerland.) 

the  head,  thorax  and  tip  of  the  abdomen  pinkish,  and  with  spines 
on  the  head,  appendages,  and  abdomen  as  illustrated.  The  pupae 
are  most  al)undant  in  New  York  during  June,  the  pupal  stage 
lasting  about  two  weeks. 

Control. — Extensive  experiments  made  by  several  investigators 
have  shown  that  the  beetles  may  be  very  largely .  destroyed  by 
thorough  spraying  with  arsenate  of  lead  just  as  they  appe^. 
By  applying  the  poison  when  they  are  first  noticed  feeding  they 
may  be  killed  off  before  many  of  the  eggs  are  laid,  and  sprayed 
vineyards  have  shown  a  reduction  of  over  90  per  cent  of  the  eggs 
found  on  untreated  vines.     Ai-senate  of  lead  should  be  applied  at 


INSECTS  INJURIOUS  TO  THE  GRAPE 


507 


the  rate  of  4  pounds  to  the  barrel  as  soon  as  feeding  marks 
are  found  on  the  foliage,  and  again  a  week  or  ten  days  later,  and 
should  be  addetl  to  the  Bordeaux  mixture  used  for  the  diseases 
of  the  vine.  The  sprayii?  must  be  done  with  the  greatest 
thoroughness,  as  the  beetles  dislike  the  sprayed  foliage  and  will  seek 
out  that  which  has  been  missed.     The  nozzles  on  traction  outfits 


Fig.  365. — A  geared  horse-power  vineyard  sprayer.  This  is  provided  with 
a  compressed  air  tank  and  an  extra  nozzle  on  each  side  directed  down- 
ward in  order  to  spray  the  tops  of  the  vines.  (After  Quaintance  and 
Shear,  U.  S.  Dept.  Agr.) 

should  therefore  be  arranged  so  as  to  hit  all  parts  of  the  vines  (see 
Figs.  365,  366)  and  the  pump  should  maintain  at  least  100  pounds 
pressure.  With  the  machines  in  common  use  not  over  7  or  8 
acres  a  day  may  b;>  covered  thoroughly,  and  about  125  gallons 
will  be  required  per  acre.     If  the  work  is  hurried  to  cover  greater 


508        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

acreage,  the  treatment  will  usually  be  less  effective.  The  beetle 
is  noticeably  less  destructive  in  well-cultivated  vineyards,  and 
it  has  been  shown  that  thorough  cultivation  in  early  summer 
breaks  up  the  pupal  cells  and  destroys  large  numbers  of  the  jDupse. 
Most  of  the  pupae  are  within  2  or  3  inches  of  the  surface  and  within 
1^  or  2  feet  from  the  base  of  the  vine.  In  the  fall  the  earth  should 
be  thrown  toward  the  vines  to  form  a  ridge  along  the  row, 
so  that  the  larvae  will  mostly  pupate  near  the  surface  of  this  ridge. 


V  >  ,     - 


Fig.  366. — A  compressed-air  sprayer  in  operation,  showing  proper  arrange- 
ment of  nozzles  for  thoroughly  spraying  grapes.  (After  Quaintance 
and  Shear,  U.  S.  Dept.  Agr.) 

The  next  spring,  when'most  of  the  larvae  have  entered  the  pupal 
stage,  this  ridge  should  be  thrown  away  from  the  vines,  thus 
exposing  the  pupae.  A  "  horse-hoe  "  commonly  used  in  vine- 
yards is  useful  in  this  work,  but  a  hand-hoe  will  need  to  be  used 
to  throw  the  earth  away  from  the  immediate  base  of  the  vine. 
The  soil  should  then  be  kept  well  stirred  by  cultivation  at  frequent 
intervals,  all  of  which  is  merely  part  of  good  practice,  independent 
of  the  control  of  the  root-worm. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


500 


The  Grapecane  Gall-maker  * 

The  Grapecane  Gall-maker  is  a  small   reddish-l)i-()wn   snout- 
beetle  about  one-eighth  inch  long,  which  lays  its  eggs  in  the  caucus, 


Fig.  367. — The  grapecane  gall-maker  (Ampeloglypter  sesostris  Lee):  a, 
adult  from  above;  6,  same,  side  view;  c,  larva,  side  view;  d,  pupa;  e, 
section  of  vine  showing  galLs — all  enlarged.  (After  F.  M.  Webster); 
/,  section  of  cane  showing  newly  made  wound  and  egg  in  lower  chamber — 
natural  size.     (After  Brooks.) 

giving  rise  to  galls  about  twice  the  diameter  of  the  cane  and  1  or 
1|  inches  long,  with  a  deep  scar  in  one  side.     It  has  been  noted 

*  Ampeloglypter  sesostris  Lee.  Family  Curculionidce.  See  Fred  E.  Brooks, 
Bulletin  119,  W.  Va.  Agr.  Exp.  Sta.;  F.  M.  Webster,  Bulletin  116,  Ohio  Agr. 
Exp.  Sta. 


510        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

as  injurious  in  Ohio  and  West  Virginia,  and  from  the  records 
seems  to  be  generally  distributed  over  the  Eastern  States,  but  is 
by  no  means  a  serious  pest. 

Life  History. — The  adult  beetles  appear  in  May  and  are  gone  by 
early  July.  They  feed  sparingly  on  the  vine,  making  little  pits  in 
the  tendrils,  in  the  buds  or  bark  of  new  canes  or  in  the  midribs  on 
the  under  side  of  the  leaves.  The  females  soon  lay  their  eggs  and 
make  the  egg  scars.  These  cause  the  galls  and  constitute  practically 
the  only  injury  to  the  vine.  The  eggs  are  laid  just  above  a  joint  and 
beyond  the  outermost  fruit,  so  that  the  injury  does  not  interfere 
with  the  crop.  A  female  eats  out  a  small  hole  with  her  snout, 
in  it  lays  a  small  yellowish-white  egg,  and  fills  up  the  hole  with 
fibers  scraped  off  from  the  surface  of  the  cane.  She  then  makes 
another  hole  immediately  above  this,  but  merely  places  a  drop  of 
liquid  in  it  and  then  fills  it  up  with  fibers  in  the  same  manner. 
Eight  to  a  dozen  holes  are  thus  made  in  a  row  and  filled.  Very 
soon  this  wound  causes  a  swelling  of  the  vine,  but  the  gall  does 
not  reach  full  size  for  six  or  eight  weeks.  On  vines  producing 
dark-colored  fruit,  the  wood  about  the  wound  takes  on  a  purplish 
color.  The  galls  seem  to  have  but  little  effect  on  the  growth  and 
vigor  of  the  vine,  except  that  the  canes  are  more  readily  broken 
by  the  wind  or  in  pruning.  The  larva  is  a  little  yellowish-white, 
footless  grub  about  two-fifths  inch  long,  which  feeds  about  the 
egg-chamber  and  then  burrows  in  the  pith.  It  becomes  full 
grown  in  eight  to  ten  weeks,  when  it  pupates  within  the  burrow; 
the  beetle  emerges  in  late  August,  and  hibernates  over  winter. 

As  the  scar  in  the  side  of  the  gall  where  the  eggs  were  deposited 
remains  open,  a  very  large  proportion  of  the  larvae  are  sub- 
sequently parasitized  by  various  chalcis,  and  tachina-flies,  which 
will  probably  prevent  the  insect  ever  becoming  much  of  a  pest. 

Control. — The  galls  may  be  cut  out  and  burned  during  July 
or  August  without  any  injury  to  the  crop,  as  they  occur  beyond 
the  fruit,  and  at  that  time  will  contain  the  larvae  or  pupae.  As  the 
beetles  feed  on  the  foliage  and  new  growth  it  is  probable  that 
but  little  damage  will  result  in  vineyards  well  sprayed  with  arsen- 
ieals  for  other  pests. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


511 


The  Grapecane  Girdler  * 

This  beetle  is  very  similar  to  the  last  except  that  it  is  black 
in  color.  Its  native  food-plant  is  the  Virginia  creeper,  which 
it  has  deserted  in  West  ^'irginia,  antl  occasionally  elsewhere, 
to  attack  grape.  The  species  seems  to  occur  generally  through 
the  Central  and  Eastern  States. 

Life  History. — The  life  history  is  almost  identical  with  that 
of  the  preceding  species,  the  habit  of  the  species  differing  only 
in  the  manner  of  oviposition.     The  eggs  are  laid  in  late  May  and 


Fig.  368. — The  grapecane  girdler  {Atupelorjlypter  ater  Lee):  a,  egg;  b,  larva; 
c,  pupa;   d,  beetle — all  enlarged.     (After  Brooks.) 

early  June.  In  laying  the  egg,  the  female  deposits  it  in  the  same 
manner  as  does  the  previous  species,  and  then  instead  of  placing  a 
series  of  holes  in  a  row  she  makes  them  in  a  ring  around  the  cane, 
only  the  first  one  containing  an  egg.  She  then  goes  to  the  next  joint 
above  and  makes  a  series  of  holes  around  it,  completely  severing 
it,  so  that  it  hangs  by  a  shred  and  soon  drops.  The  little  larva 
feeds  in  the  pith  of  the  joints  on  either  side  of  the  egg  puncture, 
and  these  two  joints  die  and  drop  to  the  ground.  The  larva 
l)ecomes  full  grown  in  about  a  month  and  changes  to  a  pupa  in 

*  Ampelaglypter  ater  Lee.     Family  Curculionidce.     See  Fred  E.  Brooks, 
Bulletin  119,  AV.  Va.  Agr.  Exp.  Sta. 


512         INSECT  PESTS   OF   FARM,   GARDEN    AND   ORCHARD 

I 


Fig.  369. — Work  of  the  g^apeoane  girdler.     (After  Brooks.) 


yJs^, 


Fig.  370. — Work  of  the  grapecane  gu'dler.     (After  Brooks.) 


l^' SECTS  INJURIOUS  TO  THE  GRAPE  513 

its  burrow  soon  aft{>r  the  dead  section  drops,  first  filling  the  burrow 
with  little  pellets  of  fibers.  Two  weeks  later  the  adult  beetle 
emerges,  appearing  during  late  summer.  The  whole  life  cycle 
thus  requires  sixty-five  to  seventy  days.  The  beetles  hibernate 
over  winter. 

Control. — The  injured  canes  are  quite  conspicuous  in  early 
summer  and  by  cutting  them  off  a  few  inches  below  the  egg  scars 
the  eggs  and  larva)  may  be  removed  and  destroyed.  Brooks 
is  of  the  opinion  that  the  beetles  will  be  largely  destroyed  in  vine- 
yards thoroughly  sprayed  with  arsenicals  for  other  grape  insects. 

The  Grape  Cane-borer  * 

During  the  spring  yoiuig  grape  shoots  sometimes  suddenly  break 
off  or  droop  and  die,  and  if  examined  a  small  hole  will  be  found  just 
above  the  base  of  the  withered  shoot,  with  a  burrow  leading 
from  it  into  the  main  stem.  In  this  burrow  will  be  found  a  small 
brown  beetle,  a  half  inch  long  (Fig.  371,  a),  which  is  the  cause 
of  the  injur}'.  It  has  been  sometimes  called  the  apple  twig-borer 
on  account  of  the  similar  injury  which  it  does  to  apple  twigs, 
and  it  also  attacks  pear,  peach,  plum,  forest  and  shade  trees  and 
ornamental  shrubs,  but  it  is  particularly  destructive  to  the  grape. 
Its  injury  is  most  noticed  in  winter  and  early  spring,  and  fre- 
quently results  in  killing  all  the  new  growth  and  sometimes 
the  entire  vine.  Injury  has  been  most  severe  in  the  States  border- 
ing the  Mississippi  from  Iowa  southward,  where  it  is  one  of  the 
most  serious  insect  pests  of  the  vine,  and  though  the  beetle  occurs 
eastward  to  the  coast  it  rarely  does  much  damage  farther  east. 

"  It  breeds  in  dying  wood,  such  as  large  prunings,  diseased 
canes,  and  also  in  dying  or  drying  wood  of  most  shade  and  fruit 
trees.  It  has  also  been  found  by  the  writer  [Marlatt]  breeding 
very  abundantly  in  roots  of  uprooted  maples  and  in  diseased 
tamarisk  stems.  In  old,  dr}-  wood  it  will  not  breed,  so  far  as 
known,  nor  in  vigorous  live  growth,  but  seems  to  need  the  dying 

*  Amphicerus  hicaudatus  Say.  Family  Ptlnidoe.  See  C.  L.  Marlatt, 
Farmers'  Bulletin  70,  U.  S.  Dept.  Agr. 


514         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

and  partially  drying  conditions  nientionotl.  The  insect  has  but 
one  brood  yearly.  The  beetles  mature  for  the  most  part  in  the 
fall,  and  generally  remain  in  their  larval  burrows  until  the  follow- 
ing spring.     A  few  may  leave  the  burrows  in  the  fall  and  con- 


FiG.  371. — The  gi'ape  cane-borer  (Amphicerus  bicaudatus  Say):  a,  beetle, 
back  and  side  views;  b,  pupa;  c,  larva,  with  feet  enlarged;  (/,  burrow  in 
apple  twig  made  by  adult;  e,  larval  gallery  in  tamarisk,  with  pupa  in 
cell  at  end;  /,  injury  to  young  shoot  and  cane  showing  entrance  of  beetle 
near/,  and  the  characteristic  wilting  and  new  growth— all  much  enlarged 
except  d,  e,f.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

struct  others  in  the  twigs  of  apple  or  other  plants  in  which  to 
hibernate.  In  the  spring,  however,  they  begin  their  destructive 
work  early,  burrowing  into  the  axils  of  the  grape  and  occasionally 


INSECTS  INJURIOUS  TO  THE  GRAPE  515 

also  into  other  plants.  This  is  undoubtedly  partly  for  food,  but 
seems  largely  malicious,  for  it  certainly  has  nothing  to  do  with 
egg-laying.  ,  .  ,  The  eggs  are  laid  chiefly  in  May  or  April  in 
its  southern  range,  and  the  larvae  develop  during  summer,  trans- 
forming to  beetles  and  pupse  in  the  fall.  On  the  Pacific  coast 
a  closely  allied,  but  somewhat  larger  species  (Amphicerus  puncti- 
'pennis  Lee.)   .  .  .  probably  has  similar  .  .  .  habits  .  .  ." 

Control. — All  diseased  wood  and  prunings  should  be  i-emoved 
in  late  spring,  thus  destroying  the  material  in  which  the  larvae 
develop.  If  this  is  neglected  and  the  beetles  appear  in  the  vine- 
yard, the  only  means  of  stopping  their  depredations  is  to  cut 
out  by  hand  the  affected  parts  and  destroy  the  beetles.  On 
warm  days  the  beetles  may  sometimes  be  collected  while  running 
over  the  vines. 

The  Grapevine  Flea-beetle  * 

When  the  grape  buds  are  swollen  in  the  spring  they  are  often 
attacked  by  numbers  of  little  blue  or  greenish  beetles  which  eat 
out  or  entirely  consume  them.  When  abundant  these  little  beetles 
may  destro}'  all  the  buds  on  a  vine,  thus  greatly  retarding  the 
leafing  out  or  even  occasionally  killing  the  plant.  The  beetle 
is  about  one-fifth  inch  long,  of  robust  shape,  and  possesses  the 
thick  thighs  characteristic  of  flea-beetles,  which  enable.it  to  jump 
a  considerable  distance  when  disturbed.  It  is  common  through- 
out the  States  east  of  the  100th  meridian  and  nearly  related 
species  do  similar  damage  on  the  Pacific  Coast.  (See  Quayle, 
I.e.)  The  wild  grape  is  undoubtedly  the  natural  food-plant  of 
the  species,  though  it  is  occasionally  found  on  plum,  apple,  pear, 
quince,  blue  beech  and  elm. 

Life  History. — After  feeding  a  few  days  the  female  beetles 
commence  to  lay  their  eggs  in  cracks  of  the  bark  at  the  base  of 
the  buds,  or  in  any  crevice  or  in  the  cavity  eaten  out  of  the  bud 
by  the  beetle,  or  sometimes  on  the  foliage.     The  eggs  are  a  long 

*  Haltica  chalybea  111.  Family  Chrysomelidce.  See  Quaintance,  I.e.; 
Hartzell,  I.e.;  and  M.  V.  Slingerland,  Bulletin  157,  Cornell  Univ.  Agr.  Exp. 
Sta. 


516        INSECT  PESTS  OF  FARM,    GARDEN  AND  ORCHARD 

oval  shape,  one-fortieth  inch  long,  and  of  a  dark  siraw-yellov.' 
color.  The  eggs  hatch  just  as  the  young  leaves  are  expanding, 
and  upon  them  the  young  larva)  feed  greedily.  The  larvio  feed 
on  the  upper  surface  of  the  leaf,  eating  out  irregular  holes  through 
the  skin  and  into  the  soft  tissue,  and  become  full  grown  in  three 
or  four  weeks.  The  young  larvsB  are  a  very  dark  brown,  but 
when  grown  they  are  one-third  inch  long  and  a  dark  yellowish- 
brown,   marked  by  regular  rows  of  blackish  tubercles  each  of 


Fig.  372. — The  grapevine  flea-beetle  (Hallica  chalybea  111.):  a,  adult  with 
hind  leg  at  right  further  enlarged;  b,  larva,  much  enlarged;  c,  beetles 
and  larvae  on  foliage — natural  size;  d,  beetle  feeding  on  bud;  e,  diseased 
beetles.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

which  bears  a  small  hair.  The  head,  anal  and  prothoi-acic 
plates  and  legs  .are  black.  The  full-grown  larva  drops  to  the 
ground  and  an  inch  or  two  beneath  the  surface  makes  a  small 
cell  in  which  it  transforms  to  a  white  pupa,  from  which  the  adult 
beetle  emerges  in  one  or  two  weeks.  In  New  York  there  is  but 
a  single  generation,  but  more  than  one  generation  may  occur  in 
the  South.     Upon  emerging  the  beetles  feed  on-  the  grape  and 


INSECTS  INJURIOUS  TO  THE  GRAPE 


517 


other  plants,  doing  no  particular  damage,  and  enter  hibernation 
in  the  fall. 

Control. — Where  vineyards  are  regularly  sprayed  with  ars(>n- 
icals  there  will  be  but  little  trouble  with  the  flea-beetles,  as  the 
grubs  are  very  easily  destroyed  on  the  foliage.  In  neglected 
vineyards  the  beetles  often  become-  very  abundant  and  may  be 
quite  destructive  in  such  locaHties.  "Where  it  is  necessary  to 
combat  the  -beetles  to  prevent  injury  to  the  buds,  close  watch 
should  be  kept  for  them  and  the  buds  should  be  thorough!}' 


Fig.  373. — Eggs  of  the  grapevine  flea-beetle,  natural  size  at  a,  and  enlarged 
at  h.     (After  Slingerland.) 

sprayed  at  once,  using  8  pounds  of  arsenate  of  lead  per  barrel. 
Usually  this  will  need  to  be  applied  just  as  the  buds  are  becoming 
well  swollen,  and  must  be .  applied  promptly  and  thoroughly, 
as  the  beetles  work  quickly  and  a  day's  delay  may  mean  the 
destruction  of  the  buds.  In  a  small  vineyard  or  on  a  few  vines 
the  l)eetles  may  l)o  collected  ]:)y  hand  in  the  early  morning  when 
they  are  sluggish,  or  may  be  jarred  to  canvas-covered  frames 
kept  saturated  with  kerosene  placed  l)eneath  the  vines. 


518  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Rose-chafer  * 

About  the  time  the  grape  is  in  bloom,  immense  swarms  of 
the  common  Rose-chafers  or  Rose-])ugs  often  appear,  covering  the 
plants,  feeding  on  the  blossoms,  later  attacking  the  young  fruit 
and  foliage,  and  sometimes  eating  the  leaves  quite  bare  except 
the  larger  veins.  The  chief  damage,  however,  is  done  by  destroy- 
ing the  blossoms  or  newly  set  fruit,  or  by  so  injuring  the  young 


Fig.  374. — The  rose  chafer  {Macrodactylus  subspinosus  Fab.):  a,  beetle; 
b,  larva;  c,  d,  mouth-parts  of  same;  e,  pupa — all  much  enlarged;  /, 
beetles  at  work  on  foliage — natural  size.    (After  Marlatt.U.S.Dept.Agr.) 

berries  that  they  are  misshapen  and  worthless.  The  beetle  is 
about  one-third  inch  long,  of  a  light-brownish  color,  covered 
with  numerous  lighter  hairs,  and  has  very  long  spiny  legs,  which 
alwa}'s  seem  to  be  in  its  way  and  make  it  most  awkward  and 
clumsy.     It  is  a  very  general  feedei",   l)eing  common  on  roses, 

*  Macrodactylus  subspinosus  Fab.  Family  Scaraboeidce.  See  Quaintance, 
I.e.;  Hartzell,  I.e.;  J.  B.  Smith,  Bulletin  82,  N,  J.  Agr.  Exp.  Sta.;  and 
Fred  Johnson,  Bulletin  97,  Part  III,  Bureau  of  Entomology,  U.  S.  Dept.  Agr 


INSECTS  INJURIOUS  TO  THE  GRAPE  519 

from  which  the  comnioii  nanic  is  rcceivctl,  and  also  on  such  orna- 
mentals as  Spiraea  and  Deutzia,  while  it  frequently  injures  the 
blossoms  of  apple,  plums,  cherries  and  peaches,  and  when  very 
abundant  will  attack  various  vegetables,  grasses,  and  grains. 
The  species  occurs  commonly  from  Canada  to  Virginia  and  Tennes- 
see and  westward  to  Colorado,  antl  in  Texas  and  Oklahoma,  but 
seems  to  do  but  little  damage  west  of  the  Mississippi,  being  most 
injurious  in  the  Middle  States.  It  is  particularly  destructive 
where  there  are  areas  of  light  sandy  soil  grown  up  in  grasses  and 
weeds,  upon  the  roots  of  which  the  larvte  feed. 

Life  History. — After  feeding  three  or  four  weeks  the  beetles 
suddcnh'  disappear.  During  the  middle  of  June,  in  New  Jersey, 
the  females  la}'  from  12  to  20  eggs,  depositing  them  in  the  soil 
singly.  These  hatch  in  two  to  three  weeks  and  the  larvae  feed 
on  the  roots  of  various  grasses  and  possibly  weeds  and  other 
vegetation.  They  become  nearly  full  grown  by  fall,  when  they 
go  below  the  frost  line  and  hiljcrnatc  over  winter.  The  larva 
looks  very  much  like  a  small  white  grulj,  which  it  closely  resembles 
in  every  wa}',  and  is  about  three-quarters  inch  long  when  full 
grown  (Fig.  374,  6).  In  the  spring  the  grubs  come  near  the  sur- 
face of  the  soil  and  enter  the  pupa  stage,  which  lasts  from  ten  to 
thirty  days  according  to  the  temperature.  There  is  but  one  genera- 
tion a  year,  and  th(^  injury  is  done  by  the  beetles  during  the  three 
or  four  weeks  they  are  abroad. 

Control. — When  the  beetles  are  very  abundant  the  only 
satisfactory  method  of  control  is  to  pick  them  by  hand  or  jar 
them  from  the  vines  onto  frames  from  which  they  may  be 
collected.  In  jarring,  an  umbrella-shaped  frame  covered  with 
canvas  or,  preferably,  oilcloth,  which  slopes  to  a  can  of  kerosene 
at  the  bottom,  is  often  used,  being  somewhat  similar  to  that  used 
for  the  plum  curculio.  This  is  held  under  the  vines  and  they  are 
sharply  jarred  or  shaken,  when  the  beetles  will  drop  to  the  frame, 
particularly  in  early  morning.  Handpicking  into  a  can  of  kero- 
sene and  water  is  probably  the  most  common  method,  however. 
Where  the  beetles  are  not  excessively  abundant  they  have  been 
controlled  in  some  cases  by  thorough  spraying  with  arsenate 


520        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

of  lead,  5  to  10  pounds  per  barrel,  preferably  applied  with  Bor- 
deaux mixture,  and  recent  experiments  of  the  N.  Y.  Agricultural 
Experiment  Station  with  5  poimds  of  arsenate  of  lead  and  12 
pounds  of  glucose  per  barrel  gave  excellent  results.  The  numbers 
of  the  pest  may  also  be  much  reduced  by  keeping  down  the  grass 
and  weeds  in  the  vineyard,  and  particularly  on  light  sandy  soils 
adjoining  lands  should  be  broken  up  and  cultivated  in  annual 
crops  as  far  as  possible,  thus  reducing  the  breeding  grounds  of  the 
pest.  By  bagging  the  grapes  as  soon  as  the  fruit  is  set  the  clusters 
may  be  protected  from  this  as  well  as  other  pests  and  diseases 
wherever  such  treatment  is  practicable. 

The  Grape  Leaf -hopper  * 

Wherever  the  grape  is  grown  in  the  United  States  and  Canada, 
the  foliage  will  be  found  more  or  less  infested  with  the  small 
Leaf -hoppers,  often  locally  called  "  thrips,"  which  feed  and  breed 
on  the  under  surface  of  the  leaves  during  the  season.  By  late 
summer  the  vines  may  be  covered  with  the  hoppers,  which  will 
fly  off  in  clouds  when  disturbed,  and  every  year  there  is  serious 
inj\ny  in  various  localities.  The  injury  is  done  by  the  little 
hoppers  sucking  out  the  juices  of  the  leaves  through  their  tube- 
like mouth-parts.  A  small  white  spot  first  appears  around  the 
feeding  puncture,  due  to  the  loss  of  chlorophyll  in  the  leaf,  and 
when  the  punctures  have  become  numerous  the  leaf  has  a  varie- 
gated appearance.  As  the  injury  increases  the  leaf  yellows  and 
finally  dries  up  and  falls  to  the  ground.  Where  it  becomes 
general,  this  injury  reduces  both  the  quantity  and  quality  of  the 
fruit.  The  pest  is  an  insidious  one,  as  it  is  not  usually  noticed 
until  it  becomes  very  abundant  in  late  summer,  by  which  time 
most  of  the  injury  has  been  done  and  it  is  too  late  to  prevent  it. 
For  this  reason  its  control  has  been  very  generally  neglected  by 
grape  growers  with  a  consequent  loss  the  cause  of  which  is  often 
unsuspected. 

"^  *  Typhlocyba  comes  Say.  Family  J  ass  idee.  See  Quaintance,  I.e.;  Hartzell, 
I.e.;  Quayle,  I.e.;  and  M.  V.  Slingerland,  Bulletin  215,  Cornell  Univ.  Agr. 
Exp.  Sta. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


521 


The  adult  hoppers  are  about  one-eighth  inch  long  and  the 
wings  are  prettily  marked  with  yellow  and  red  as  shown  in  Fig. 
375.  "  In  summer  the  young  and  adult  insects  are  light  yellowish 
in  color,  but  before  going  into  hil)ernation,  the  eyes  of  the  adults 
darken  and  the  peculiar  j'ellow  spots  on  the  wings  change  to  an 
orange  red,  thus  giving  the  hibernating  adidts  a  general  reddish 
appearance.  These  darker  markings  on  the  adults  vary  so  much 
that  nine  different  varieties  are  now  recognized,  two  of  which  are 
represented  at  h  and  c,  in  Fig.  375.    Often  several  of  the  varieties 


Q  Fig.  375. — Grape  leaf-hopper  {Typhlocyba  cnmes):  a,  adult  female;  h,  adult 
male;  c,  another  form  of  the  species,  showing  variation  in  markings; 
d,  newly-hatched  nymph;  e,  last  stage  nymph;  /,  appearance  of  injured 
leaf;  g,  cast  pupa  skins — a,  e,  much  enlarged;  g,  less  enlarged;  /,  reduced. 
(From  Marlatt,  U.  S.  Dept.  Agr.) 

may  be  found  together  on  the  same  vines,  but  usually  one  color 
form  largely  predominates."  The  nymphs  are  a  light  yellowish- 
green  color  with  lemon-yellow  stripes  on  each  side  of  the  body. 
They  pass  through  five  molts  before  becoming  adults,  the  wing- 
pads  gradually  getting  larger  in  the  later  stages.  No  very  similar 
insects  are  common  on  the  grape,  so  that  the  pest  is  readily  recog- 
nized. 

Life  Hislori/. — The  adult  hoppers  hibernate  over  winter  under 
leaves,  grass,  or  trash  in  or  near  the  vineyard,  in  neighboring 


522         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

woods,  along  ditches  or  fences,  etc.  They  emerge  about  May  1 
in  New  York  and  at  first  feed  on  whatever  succulent  foliage  may 
be  available.  By  the  time  the  grape  foliage  appears  they  have 
mostly  emerged  and  infest  the  vineyards.  These  hibernating 
hoppers  feed  and  breed  on  the  lower  leaves,  disappearing  about  the 
time  the  first  young  become  adult.  After  a  few  weeks  the  females 
commence  egg-laying,  which  continues  for  about  two  months. 
The  eggs  arc  laid  just  beneath  the  surface  of  the  leaf  in  groups 
of  from  six  to  nine,  or  singly,  and  as  they  are  but  onc-thirty-fifth 
inch  long  and  almost  transparent,  they  are  scarcely  visible  save 
for  the  eyes  of  the  eml^ryonic  nymphs.  The  eggs  hatch  in  nine  to 
fourteen  days.  The  young  nymphs  feed  like  the  adults,  at  first 
on  the  lower  leaves,  but  soon  spread  to  all  parts  of  the  plant. 
In  New  York  they  become  grown  in  thirty  to  thirty-five  days, 
and  there  is  but  one  full  generation  a  year,  with  a  partial  second 
generation,  most  of  the  individuals  of  which  probal^ly  do  not 
mature  before  frost.  Feeding  continues  until  cool  weather,  when 
the  adults  enter  hibernation.  In  Colorado,  New  Mexico  and 
California  and  prol^ably  throughout  the  South,  there  are  two  full 
generations  a  year.  In  California,  according  to  Quayle,  the 
nymphs  from  eggs  laid  by  the  hibernating  hoppers  appear  by  the 
middle  of  May  and  the  following  generation  of  nymphs  about 
the  middle  of  July. 

Control. — Cleaning  up  all  fallen  leaves  and  trash  in  the  vine- 
yard during  the  winter,  or  plowing  it  under  in  the  early  spring, 
will  reduce  the  number  of  hibernating  hoppers,  and  it  has  been 
observed  that  they  are  much  less  numerous  in  vineyards  where 
clean  culture  is  practiced.  The  burning  over  of  adjacent  meadows, 
wood  lots  and  fence  rows  will  also  be  advisable  where  practicable. 

In  California,  where  the  vines  are  not  trellised,  a  hopper-cage, 
which  has  been  fully  described  by  Quayle,  I.e.,  is  successfully 
used  for  catching  the  hoppers  before  they  commence  to  oviposit 
in  the  spring.  In  the  East  this  could  not  be  used,  and  Professor 
Slingerland  has  shown  that  the  hibernated  hoppers  may  be  caught 
on  sticky  shields  before  they  oviposit.  "  A  light  wooden  frame 
is  made  7  or  8  feet  long  by  4  feet  high.     To  the  crosspiece  at  the 


INSECTS  INJURIOUS  TO  THE  GRAPE  523 

bottom,  which  should  l)o  up  from  the  ground  al:)Out  a  foot,  are 
fastened  several  stiff  wires  of  the  shape  of  a  hayrake  tooth.  These 
are  fastened  so  that  the  points  curve  inward  and  downward  to 
the  ground  at  the  base  of  the  plants  when  the  shield  is  held  in 
place  beside  the  vines.  The  whole  framework,  including  the 
wires,  is  covered  with  oilcloth,  which  is  coated  with  a  sticky  sub- 
stance, made  by  using  melted  resin,  1  cjuart,  and  castor  oil,  1 
pint."  Tanglefoot  might  be  used  instead.  The  hoppers  are  on 
the  lower  leaves  eai'ly  in  the  season,  so  that  the  frames  need  not 
be  high,  and  it  is  at  that  season  that  it  is  important  to  catch 
them.  The  vines  will  need  to  l)e  gone  over  frequently,  a  man 
carrying  a  shield  on  either  sitle  and  jarring  the  vines  so  that  the 
hoppers  will  fly  off  and  be  caught  on  the  shields.  The  young 
hoppers  may  be  killed  In'  spraying  with  whale-oil  soap,  1  pound  to 
10  gallons,  10  per  cent  kerosene  emulsion,  or  tobacco  extract. 
In  California  a  resin  spray  composed  of  1  pound  of  resin  antl  one- 
quarter  pound  of  lye  dissolved  in  15  gallons  of  water  is  used.  This 
work  must  be  done  with  the  greatest  thoroughness,  as  the  hoppers 
must  be  hit  to  be  killed.  Underspray  nozzles  must  be  used  and 
handled  by  men  who  will  cover  the  under  surface  of  all  the  leaves. 
This  cannot  be  done  by  fixed  nozzles,  unless  very  high  pressure 
and  many  nozzles  are  used.  The  work  is  necessarily  slow  and 
expensive  and  should  be  commenced  as  soon  as  the  young- 
appear,  when  they  may  be  more  easily  destroyed  and  when  there 
is  less  foliage  to  be  sprayed.  Several  applications  will  usually 
be  necessary. 

The  Grape  Leaf -folder  * 

Very  frequently  grape  leaves  are  found  folded  or  I'olled 
together,  with  the  interior  surface  more  or  less  skeletonized, 
from  which  a  slender  larva  will  wriggle  out  and  fall  or  hang 
suspended  on  a  silken  thread.  The  Grape  Leaf-folder  occurs 
throughout  the  United  States,  and  though  usually  not  injurious, 
sometimes   becomes   abundant   enough    to    do   serious   damage. 

*  Desmia  funeralis  Hlibner.  Family  Pyralidce.  See  Quaintance,  and 
Quayle,  I.e. 


524        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  moth  is  black  with  white  spots  on  the  wings,  and  bands  across 
the  abdomen,  as  shown  in  Fig.  376.  The  larva  is  about  an  inch 
long,  of  a  greenish-white  color,  with  head  and  prothoracic  shield 
light  brown,  and  with  brown  spots  on  the  sides  of  the  first  two 
thoracic  segments. 

Life  History. — "  There  are  two  broods  each  year  in  the  more 
Northern  States  and  three  or  possibly  more  in  the  South.  The 
insect  winters  in  the  pupal  stage  in  the  folded  and  fallen  leaves, 
the  moths  appearing  in  the  spring  shortly  after  the  foliage  puts 


Fig.  376. — The  grajje  leaf-folder  {Desmia  funeralis  Hiibn.):  a,  male  moth  and 
enlarged  antenna  of  same;  b,  female  moth;  c,  larva;  d,  head  and  thoraci'' 
segments  of  same  enlarged;  e,  pupa;  /,  tip  of  pupa — enlarged;  g,  grape 
leaf  folded  by  larva.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

out,  and  the  eggs  are  placed  in  small  patches  here  and  there 
on  the  vine.  Upon  hatching,  the  young  larvse  attack  the 
foliage,  folding  the  leaves  as  stated.  Mr.  Johnson  has  observed 
that  the  larvae  of  the  first  brood  may  attack  bunches  of  grape 
blossoms  and  young  fruit  in  a  way  similar  to  the  grape-beri-y 
moth.  In  three  or  four  weeks  the  larvse  are  full  grown  and 
transform  to  pupa3  within  the  folded  leaves,  moths  emerging 
eight  or  ten  days  later.  By  midsummer  and  fall  the  insects 
become  quite  abundant,  and  in  badly  infested  vineyards  the 
folded   leaves   are   everywhere    in    evidence  and    are  quite    con- 


INSECTS  INJURIOUS  TO  THE  GRAPE  525 

spicuous  from  the  color  of  the  lower  surface.  In  the  fall  the 
larva^  pupate  in  the  folded  leaves  and  pass  the  winter  in  these 
on  the  ground." — Quaintance. 

Control. — Where  but  a  few  larvae  occur  they  may  be  crushed 
by  hand,  and  if  this  is  done  with  the  first  brood  it  will  greatly 
reduce  the  numbers  later  in  the  season,  ^'ineyards  sprayed 
with  arsenicals  will  be  protected,  as  the  young  larva  will  be  killed 
before  they  fold  the  leaves.  By  collecting  and  burning  the  fallen 
leaves  or  plowing  them  under  deeply,  many  of  the  hibernating 
pupa^  may  be  destroyed. 

Hawk-moth  Larvae  * 

Several  species  of  Hawk-moth  or  Sphinx-moth  larva?  are  com- 
monly found  on  the  vine.  ]\Iost  of  them  are  widely  distributed 
throughout  the  country  and  feed  on  wild  grape  and  ^^irginia  creeper. 
Usually  they  are  not  numerous  enough  to  do  serious  damage, 
and  as  they  strip  a  branch  at  a  time,  they  are  readily  seen  and 
may  be  destroyed  before  nuich  injury  is  done.  Occasionally, 
however,  one  or  two  larva)  may  entirely  strip  a  }'oung  vine,  and 
exc(>ptionally  the  larvie  appear  in  consideral)le  numbers  on  old 
vines,  stripping  them  ])are  of  foliage.  They  are  large,  smooth- 
bodied  larva?,  2  to  4  inches  long,  and  may  be  distinguished 
from  those  of  other  families  of  moths  by  the  strong  horn  on  the 
next  to  the  last  segment,  which  has  given  them  the  common  name 
of  horn-worms.  In  many  species,  this  horn  is  present  onl}-  in  the 
first  one  or  two  stages  of  the  larva,  disappearing  with  the  next 
molt  and  being  replaced  by  a  bright  eye-spot,  as  shown  in  Fig.  377, 
c,  d.  The  life  history  of  the  various  species  is  much  the  same, 
except  that  some  have  only  one,  Avhile  others  have  two  genera- 
tions a  year  in  the  North,  though  most  all  probably  have  two 
generations  in  the  South.  They  hibernate  as  large  dark-brown 
pupa?,  3  or  4  inches  below  the  surface  of  the  ground,  and 
the  moths  emerge  in  spring.  The  moths  are  particularly  attracted 
to  petunias,   and  may  often   be   caught  hovering  over  them  at 

♦Family  Sphingidce.  See  O.  Lugger,  4th  Report  State  Ent.  Minn.;  Ida 
M.  Eliot  and  Caroline  M.  Soule,  "Caterpillars  and  their  Moths."  (N.  Y.,  1902). 


526        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

night.  The  eggs  are  laid  on  the  foliage,  usually  singly,  and  the 
larvae  hatch  in  a  few  days.  They  eat  ravenously,  and  will  consume 
an  enormous  number  of  leaves  within  a  few  days.     Usualh'  the 


Pre.  377. — ^The  achemon  sphinx  (Pholus  achemon  Dm.):  a,  moth;  6,  egg;  c, 
young  larva;  d,  mature  larva;  e,  pupa;  /,  parasitized  larva — all  natural 
size,     (After  Marlatt,  U.  S.  Dept.  Agr.) 

coloration  of  the  larvae  changes  more  or  less  as  they  grow,  so 
that  when  full  grown  they  are  different  from  the  younger  stages. 
When  there  are  two  generations,  the  second  generation  of  larvae 


INSECTS  INJURIOUS  TO  THE  GRAPE  527 

will  appear  in  late  July,  but  whether  one  or  two  generations  occur, 
the  larva'  maturing  in  late  summer  transform  to  pupa)  which 
hibernate. 

Control. — Usually  the  work  of  the  larvsG  is  so  conspicuous  and 
they  are  so  easily  found  that  they  may  be  controlled  by  hand- 
picking.  Where  the  vineyards  are  sprayed  regularly  for  other 
pests  there  will  be  but  little  trouble  with  these  larvae,  as  they  will 
be  killed  while  young. 

The  Achemon  Sphinx.*  This  is  one  of  the  most  common 
species  on  the  grape.  The  young  larva  is  a  light-green  color  with 
a  long  reddish-brown  horn  which  becomes  shorter  as  the  larva 
grows  and  finally  disappears  and  is  replaced  by  a  large  polished 
eye-spot.  The  mature  larva  is  about  3+  inches  long,  and  varies 
in  color  from  straw-color  to  reddish-brown.  Along  the  sides  are 
six  diagonal  cream-colored  spots,  on  the  second  to  seventh  abdom- 
inal segments  inclusive.  The  body  is  much  wrinkled  and  dotted 
with  small  spots,  dark  on  the  back  and  lighter  on  the  sides.  The 
head  and  first  two  thoracic  segments  are  small  and  are  retracted 
into  the  metathorax  when  at  rest.  Just  before  pupation  the 
larva  becomes  a  pink  or  crimson  color.  The  moth  has  a  wing 
expanse  of  3  inches  and  is'  l)rownish-gray,  \'ariegated  with  light 
brown,  and  deep  brown  spots;  the  hind  wings  are  pink,  with  a 
dark  shade  across  the  middle,  still  darker  spots  below  this,  and 
a  broad  gray  band  behind.  The  body  is  reddish-gray  with  tri- 
angular brown  patches  at  the  base  of  the  wings,  which  are  edged 
with  white. 

The  Pandorus  Sphinx. f  This  nearly  related  species  is  also 
common  on  the  vine,  but  rarely  does  much  damage.  The  wings 
expand  4  to  4§  inches,  and  are  a  light,  olive  color,  mixed  with 
gray,  marked  with  patches  of  darker  olive  green,  and  with  portions 
of  a  rosy  hue,  especially  on  the  hind-wings.  The  body  is  light 
greenish-brown  marked  with  dark  olive  patches.  The  larva  is 
very  similar  to  that  of  the  last  species,  l)ut  has  only  five  rather 
oval  cream-colored  spots  on  the  sides  of  the  third  to  seventh 
abdominal  segments. 

*  Pholus  achemon  Dru.  t  Pholus  pandorus  Hbn. 


528        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Grape-vine  Hog  Caterpillar.*  This  is  one  of  the  most 
common  sphinx  larvae  on  grape  and  Virginia  creeper.  The  grown 
larva  is  2  inches  long,  of  a  green  color,  covered  with  small  yellow- 
dots  or  granulations.  Along  the  sides  of  the  body  are  seven 
oblique  yellowish  stripes  margined  behind  with  a  darker  green. 
A  white  stripe  with  a  deep  green  margin  extends  from  behind 
the  head  to  the  horn,  on  either  side  of  the  back,  and  along  the 
middle  are  a  series  of  seven  spots,  vaiying  in  color  from  red  to 
pale  lilac  and  each  set  in  a  patch  of  pale  yellow.  Frequently, 
especially  in  the  second  generation,  specimens  are  found  which  are 


Fig.  378. — The  grapevine  hog-caterpillar  moth  {Ampelophaga  mxjron  Cram). — • 
natural  size.     (After  Lugger). 

a  light  pinkish  instead  of  green  and  arc  marked  with  darker  shades 
of  red  and  l^rown  so  that  they  may  easily  be  mistaken  for  another 
species.  The  wings  of  the  moth  expand  2h  inches  and  are  long 
and  narrow.  The  fore-wings  are  olive  green,  crossed  by  bands 
of  greenish-gray,  while  the  hind-wings  are  dull  red  shading  to 
greenish-gray  next  to  the  body.  The  body  is  pale  green,  with 
the  head  and  shoulders  deep  olive  green. 

The  White-lined  Sphinx. f  This  species  has  a  long  list  of 
food-plants,  the  larvae  feeding  and  multiplying  on  purslane, 
chickwecd  and  other  weeds,  and  then  attacking  various  crops, 
among  which  is  the  grape.      (See  p.  247).     They  are  about  3^- 

*  Artipelophnga  myron  Cram.  |  Deilephila  lineata  Fab. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


529 


inches  long  and  quite  variable  in  color,  some  being  yellowisli-green 
with  black  e}-e-spots  along  each  side  of  the  back  and  with  faint 
l)lackish  stripes,  while  others  are  black  with  yellowish  spots,  as 
shown  in  Fig.  379.  The  moth  is  shown  natural  size.  The  fore- 
wings  are  an  olive  color  with  a  pale  buff  stripe  across  the  middle, 


Fig.  379. — The  white-lined  sphinx  (Deilephila  lineata  Fab.):  a,  moth;  b, 
pale  larva;  c,  dark  form  of  larva;  d,  pupa — all  natural  size.  (After 
Chittenden,  U.  S.  Dept.  Agr.) 

and  are  margined  with  gray,  and  the  hind- wings  are  crossed  by 
a  wide  rosy  band,  the  remainder  being  almost  black,  except  the 
white  margin.  The  thorax  is  marked  with  several  white  lines 
as  illustrated,  and  the  abdomen  is  greenish  olive  spotted  with 
white  and  black. 


530       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Abbot's  Sphinx.*  This  caterpillar  is  2^-  inches  long,  varying 
in  color  from  dull  yellow  to  reddish  l^rown.  Each  segment  is 
marked  by  six  or  seven  transverse  l)lack  lines,  and  longitudinally 
with  dark -brown  streaks.  On  the  next  to  the  last  segment  is  a  pol- 
ished black  tubercle,  or  eye-spot,  ringed  with  yelloM".  The  moth  is 
a  dull  chocolate-brown  color,  with  a  wing  expanse  of  2-^  inches. 
The  fore-wings  are  pale  beyond  the  middle 
and  are  streaked  with  darker  brown  as  illus-  : 
trated.  The  hind- wings  are  yellow  with  a 
brown  border.     The  terminal  segments   of 


Fig.  380. — Abbott's  sphinx  (Sphecodina  abbottii  Swain)  and  its  larva — natural 
size.     (After  Lugger.) 

the  abdomen  bear  tufts  of  scales  on  either  side,  making  the 
abdomen  appear  truncated  instead  of  pointed,  as  in  most  sphinx 
moths. 

The  Grape-berry  Moth  f 

The  larvie  of  the  Grape-berry  Moth  are  the  most  common 
cause  of  wormy  grapes.  The  first  generation  of  larvse  web  together 
the  grape  clusters  before  the  blossoms  open  or  soon  after 
the  grapes  are  set,  and  feed  upon  the  clusters.  Later  the  larvse 
bore  into  the  green  and  ripening  fruit,  producing  purplish  spots 
resembling  the  appearance  of  injury  by  the  Ijlack  rot.  The 
berries  decay  from  the  work  of  the  larva)  and  from  the  entrance 

*  Sphecodina  abbottii  Swain. 

t  Polychrosis  viteana  Clem.  Family  Tortricidoe.  See  Quaintance,  I.e.; 
Hartzell,  I.e.;  M.  V.  Slingerland,  Bulletin  223,  Cornell  Univ.  Agr.  Exp.  Sta.; 
and  Gossard  and  Houser,  Circular  63,  Ohio  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  THE  GRAPE 


531 


of  fungous   diseases.    The  insect  occurs  throughout  the  United 
States,  but  has  been  particularly  injurious  in  the  Chatauqua,  N.  Y., 


Fig.  381. — American  grape-berry  moth,  enlarged.     (After  Slingerland.) 

Erie,  Pa.,  and  Northern  Ohio  grape  belts.     So  far  as   known  the 
grape  is  the  only  food-plant  and  the  species  is  a  native  one,  though 

its  habits   are  very  similar  to    a        r  ...^ 

nearly  related   European  species.  ^k. 

The  adult  is  a  little  purplish- 
brown  moth,  with  wings  expand- 
ing not  quite  one-half  inch,  and 
shaded   with  brownish    markings 


Fig.  382. — The  work  of  the  grape-berry  moth;    infested  cluster  and  single 
berry  opened  to  show  larva  at  work — enlarged.     (After  Slingerland.) 

as  shown  in  Fig.  3S1.     The  ground  color  is  lilaceous  or  leaden- 
blue  and  the  spots  are  dark  brown. 


532  INSECTS  OF  FARM,  GARDEN  AND  ORCHARD 

Life  History. — The  moths  appear  in  the  spring  as  the  shoots 
of  the  grape  are  pushing  out,  and  continue  to  emerge  for  some 
weeks.  The  earli(>r  ones  lay  their  eggs  on  the  blossom  clusters, 
while  the  later  ones  deposit  them  on  the  young  grapes.  The 
minute  flat,  scale-like  eggs  are  stuck  to  the  surface  of  the  stems 
or  berries,  and  look  like  small  glistening,  whitish  spots.  The 
little  larvffi  hatching  from  them  feed  on  the  blossoms  and  small 


Fig.  383. — Grape-berry  moth  caterpillars,  enlarged.     (After  Slingerland.) 

berries,  webbing  the  clusters  togi^ther,  and  might  do  much  more 
damage  than  the  later  generations  wei'e  it  not  that  they  are  much 
fewer  in  number,  there  l)eing  a  great  moi'tality  of  the  insects  over 
winter.  The  larva?  become  full  grown  in  about  three  weeks. 
The  mature  larva  is  about  three-eighths  inch  long,  varying  in 
color  from  dark  greenish  to  dark  purplish,  with  a  light-brown 
head  and  black  thoracic  shield.  The  body  is  covered  with 
numerous  faintly  outlined  darker  spots,  from  which  arise  whitish 


INSECTS  INJURIOUS  TO  THE  GRAPE  533 

hairs,  as  shown  in  Fig.  383.  The  larva  cuts  out  a  piece  of  a  leaf  on 
three  sides,  folds  it  over  and  fastens  the  free  edge  to  the  leaf  with 
silk.  The  fold  is  then  lined  with  a  thin  layer  of  silk,  making  a 
thin  cocoon  in  which  it  transforms  to  a  light  greenish-bi'own  pupa, 
from  which  the  moth  emerges  twelve  to  fourteen  clays  later. 
The  moths  of  the  second  and  later  generations  place  their  eggs 
on  the  berries  and  the  larvae  bore  into  them  and  feed  on  the  pulp 
and  seeds.  In  Xew  York  the  moths  of  the  second  generation 
appear  in  early  July  and  the  second  generation  of  larva)  occurs 


Fig.  384. — Grape  leaf  showing  cocoons  in  the  making  and  finished  by  grape- 
berry  moth  caterpiUars — natural  size.     (After  Slingerland.) 

during  July  and  August.  In  Xew  York  those  larvne  of  the  second 
generation  which  mature  before  mid-August  pupate  and  give 
rise  to  a  third  generation,  while  those  maturing  later  transform 
to  pupse,  but  hibernate.  Often  there  is  nearly  a  complete  third 
brood  in  that  latitude,  and  further  south  there  are  undoubtedly 
at  least  three  generations.  The  winter  is  jDassed  in  the  pupal 
stage  in  the  cocoons,  which  break  off  from  the  fallen  leaves. 

Control. — Infested  berries  should  be  picked  off  both  to  destroy 
the  larva)  and  to  pre\cnt  the  spreading  of  fungous  diseases.     Plow- 


534        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

ing  under  the  fallen  leaves  either  in  fall  or  early,  spring  should 
result  in  burying  many  of  the  pupa  so  as  to  prevent  the  escape 
of  the  moths,  and  is  good  practice  for  other  grape  pests.  The 
principal  reliance  should  be  placed  upon  spraying  with  arsenate 
of  lead,  8  pounds  per  barrel,  or  one-half  pound  of  Paris  green, 
applied  with  Bordeaux  mixture,  to  which  a  soap  "  sticker " 
should  be  added  (see  p.  46)  to  make  the  mixture  more  adhesive 
to  the  berries.  The  first  spraying  should  be  made  before  the 
blossoms  open,  to  catch  the  early  larvsp;  the  second  should  be 
made  as  the  grapes  finish  l^looming;  and  the  third,  early  in  Jidy. 
The  addition  of  the  "  sticker  "  is  most  important  in  the  last 
spraying,  when  the  berries  are  partly  grown.  The  spray  must  be 
applied  with  sufhcient  numl^er  of  nozzles  and  pressure  to  penetrate 
the  foliage  and  cover  the  clusters  thoroughly.  In  a  small  home 
vineyard  the  clusters  might  ])e  protected  by  bagging  them  as 
soon  as  the  fruit  is  set. 

The  Grape  Curculio  * 

The  larvso  of  the  Grape  Curculio  feed  on  the  pulp  and  seeds  of 
the  berries,  causing  wormy  grapes,  much  as  do  those  of  the  berry- 
moth.  The  larvae  may  be  readily  distinguished,  for  those  of  the 
curculio  are  white,  footless  grubs,  while  those  of  the  berry-moth 
are  greenish,  with  well-developed  legs,  and  are  quite  agile,  wriggling 
away  quickly  when  disturbed.  The  adult  curculio  is  a  small, 
brown,  robust,  snout-beetle  about  one-tenth  inch  long,  and 
nearly  as  broad.  It  is  very  difficult  to  see,  looking  like  a  bit  of 
dirt  or  the  excreta  of  some  of  the  larger  caterpillars  common  on 
the  vine.  It  is  common  from  Arkansas  to  Minnesota  eastward 
to  New  York  and  North  Carolina.  It  has  been  particularly  in- 
jurious in  West  Virginia,  and  seems  to  be  most  harmful  in  that 
latitude. 

Life  History. — The  Ix'ctles  hibernate  over  winter  in  or  near 
the   vineyards,   especially   along  tlu^   edge   of   woodlands.     They 

*  Craponius  incequalin  Say.  Family  Curculiunidce.  See  Quaintance, 
I.e.,  and  Fred  E.  Brooks,  Bulletin  100,  W.  Va.  Agr.  Exp.  Sta, 


INSECTS  INJITUIOTTS  TO  THE  GRAPE 


535 


appear  in  the  spriiii;-  nbout  Ihc  time  the  grapes  blossom  and  feed 
upon  the  foliase  for  three  or  four  weeks  until  the  berries  are  about 


Fig.  385. — The  grape  curculio  {Craponius  incequaUs  Say):  a,  beetle;  b,  head 
of  same  from  side;  d,  larva  from  above;  e,  same  from  below;  /,  pupa — 
all  much  enlarged.     (After  Quaintance,  U.  S.  Dept.  Agr.) 

one-fourth  grown.  The  Ijectles  cut  small  characteristic  holes  in 
the  leaves,  and  this  hal)it  of  feeding  on  the  foliage  so  long  makes 
it  possible  to  kill  them  with  arsenicals  before  oviposition  is  com- 


^ 


Fig.  386. — The  grape  curcuho 
in  act  of  egg-laying — natural 
size  ;  e,  showing  position 
of  egg  in  grape — enlarged. 
(After  Brooks.) 


Fig.  387. — Grape  curcuho  larvse — 
natural  size.     (After  Brooks.) 


menced.     In    West   A'irginia    the    females    begin  egg-laying  late 
in  June,    most    of   the   eggs  l)eing  laid   in  early  July,    ])ut    egg 


63G         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

laying  may  continue  for  eigJity-onc  days,  during  which  time  a 
female  will  lay  an  average  of  257  eggs.  The  female  excavates 
a  small  cavity  in  the  berry  in  which  the  egg  is  ijlaced  and  hatches 
in  four  to  six  days.  Infested  berries  often  show  a  purplish  spot 
around  the  egg-puncture.     The  larva  bores  in  the  pulp  and  in 


Fig.  388. — Grapes  showing  egg-punctures  of  grape  curculios.     (After  Brooks.) 

three  or  four  days  reaches  the  seed,  which  is  then  devoiuvd.  The 
larva  becomes  full  grown  in  twelve  to  fifteen  days,  when  it  eats 
its  way  out  of  the  berry  and  drops  to  the  ground  in  search  of  a 
suitable  place  to  pupate.  The  mature  larva  is  white,  about  one- 
third  inch  long,  tapering  from  the  middle  of  the  Ijody  toward 
either  end,  without  legs,  and  clothed  with  fine  short  hairs.     The 


• 

• 

/ 

2. 

V 

3 

J 

Fig.  389. — Showing  the  resemblance  of  the  grape  curculios  at  2  to  excrement 
of  sphinx  caterpillars  at  1,  and  mummied  grapes  at  3.     (After  Brooks.) 

larvse  make  small  earthen  cells  under  stones,  lumps  of  earth 
or  just  below  the  surface  of  the  soil,  and  in  them  transform  to 
pupse,  from  which  the  beetles  emerge  in  eighteen  to  nineteen  days. 
Thus  the  complete  life  cycle  from  egg  to  adult  requires  thirty-five 
days.     The  hibernating  beetles   are  still  abroad  when  the  new 


INSECTS  INJURIOUS  TO  THE  GRAPE  537 

beetles  appear,  and  Brooks  states  that  the  average  life  of  a  beetle 
is  one  year  and  nineteen  days.  Although  the  beetles  of  the  new- 
brood  lay  some  eggs,  l)ut  few  of  them  develop,  and  in  West 
Virginia  there  is  practically  but  one  generation,  although  farther 
south  a  second  generation  may  occur.  The  beetles  feed  until 
fall,  when  they  enter  hil^ernation. 

Control. — As  the  beetles  feed  so  long  on  the  foliage  in  early 
summer  they  may  be  readily  killed  by  spraying  with  arsenicals 
as  advised  for  the  berry-moth  and  grape  root-worm  beetle. 
Thorough  cultivation  in  niidsummor  would  doubtless  destroy 
some  of  the  pupie  in  tlu^  same  manner  as  in  the  case  of  the  root- 
worm.  Infested  fruit  may  be  collected  and  destroyed  as  for 
the  berry -moth  with  equally  good  results.  Where  spraying  is 
regularly  practiced  there  prol^ably  will  be  little  need  of  resort  to 
other  method*.  . 


CHAPTER  XXVI 

SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 

The  San  Jose  Scale  * 

Probably  the  most  serious  of  all  th(^  insect  pests  of  the  orchard 
is  the  San  Jose  Scale,  for  it  will  kill  young  trees  in  two  or  three 
years,  and  old  trees  must  be  sprayed  annually  to  keep  it  under 
conti-ol.  So  insidious  is  the  attack  of  the  pest  to  those  unfamiliar 
with  it  that  it  has  killed  many  thousands  of  trees  before 
the  owners  suspected  its  presence.  It  may  be  most  readily 
detected  on  the  fruit,  which  l)ecomes  spotted  with  small  red 
circles  which  form  around  the  scales,  but  usually  the  fruit  is 
not  attacked  until  the  tree  is  badly  infested.  On  the  young 
twigs  and  along  the  veins  of  the  leaves  a  similar  reddish  discolor- 
ation appears  around  the  scales.  The  trunk  and  branches  covered 
with  scales  have  a  rough  grayish  appearance,  as  if  they  had  lieen 
coated  with  dark  ashes.  By  scraping  the  surface  the  soft,  juic}-, 
•\-ellowish  insects  will  be  revealed  beneath  the  covering  scales. 
If  a  single^  female  insect  be  examined  it  w'ill  be  found  that  it  is 
covered  1)}-  a  small,  circular  scale,  varying  from  grayish  to  Ijlackish 
in  color,  formed  of  concentric  circles,  the  centre  of  which  is  cjuite 
convex  and  forms  a  "  nipple,"  which  is  yellowish  and  shining 
when  the  surface  is  rubbed  off.  If  this  scale  l^e  raised  with  a 
pin,  beneath  it  may  be  seen  a  small,  soft,  oval,  orange-colored, 
object,  which  is  the  true  female  insect.  She  is  an  almost  shape- 
less mass  of  protoplasm,  lacking  head,  legs,  and  eyes,  only 
the  thread-like  mouth  parts  and  anal  plate  being  distinct.     The 

*  Aspidiotus  perniciosus  Comstock.  Family  Coccidos.  Sec  C.  L.  Mar 
latt,  Bulletin  62,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  and  the  numer- 
ous publications  of  many  of  the  experiment  stations,  listed  in  his 
bibliography. 

538 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS       539 


scale  itself  is  merely  a  waxy  covering  secreted  by  the  insect 
beneath.  The  scale  of  the  male  is  smaller  and  somewhat  elongated, 
the  nipple  being  at  the  larger  end. 

Injury  by  this  species  was  first  noticed  near  San  Jose,  Gal., 


Fig.  390. — Peach  twigs  infested  with  the  San  Jose  scale.  On  the  twig  at 
the  right  a  scale  has  been  turned  back  showing  the  female  insect — 
enlarged.     (After  W.  E.  Britton.) 

about  1S80,  where  the  scale  was  most  destructive  and  was  investi- 
gated by  Professor  J.  H.  Comstock,  who  first  described  it.  About 
1887  it  was  brought  east  on  Japanese  plum  trees  secured  by 
Eastern  nurseries  and  was  distributed  loy  them  on  3'oung  trees, 


540         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


so  that  in  1893  it  was  discovered  in  orchards  in  Maryland  and 
Virginia.  Since  then  it  has  been  spread  on  nursery  trees  to 
practically  every  State.  Investigations  made  by  C.  L.  Marlatt 
in  1901  showed  that  the  insect  is  undoubtedly  a  native  of  east- 
central  China,  and  was  probably  brought  to  this  country  on  flower- 
ing peach  or  some  ornamental  plant. 

Life  History.  The  winter  is  passed  as  partly  grown  insects 
under  the  scales,  which  begin  to  feed  with  the  bursting  of  the 
buds  in  spring.  In  the  latter  part  of  April  the  insects  have  become 
full  grown  in  the  District  of  Columlwa,  and  the  males  emci'ge  and 
fertilize  the  females.     The  male  is  a  small,  yellowish,  two-winged 

fly,  similar  to  Fig.  448«.  The  males 
emerge  at  night  and  are  so  small 
they  are  sekloni  seen  unless  n^ared. 
About  a  month  later  the  females 
commence  to  give  birth  to  live 
3'oung  an(,l  continue  to  do  so  for 
some  six  weeks.  This  species  differs 
from  most  scales  in  having  no  egg 
stage,  the  eggs  hatching  in  the  body 
of  the  female.  The  young  insects 
are  very  small,  yellowish  in  color, 
and  resem])le  small  mites.  They 
have  si-x  legs,  a  pair  of  antenna?, 
and  a  long  thread-like  beak  through 
which  the  food  is  sucked,  as  shown 
in  Fig.  394.  The  young  insect  moves  about  freely  for  from  twelve 
to  thirty-six  hours,  then  thi-usts  its  beak  into  the  l)ark  or  fruit,  and 
if  a  female  does  not  move  again.  White,  waxy  filaments  soon 
exude  from  over  the  body,  and  in  a  couple  of  days  the  insect  is 
entirely  covered  by  them,  and  as  they  mat  down  a  scale  is  formed 
which  conceals  it.  This  young  scale  is  whitish  with  a  prominent 
nipple  in  the  center.  After  the  first  molt,  the  females  lose 
eyes,  legs,  and  antennae,  for  Avhich  they  have  no  further  .  use. 
Nourished  by  the  sap  of  the  plant  the  insect  develops  rapidly  and 
is  full  grown  in  about  a  month.     In  the  District  of  Columbia 


Fig.  391. — Pear  injured  by  the 
San  Jose  scale  showing  the 
discolored  spots. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS      541 

there  are  four  or  five  generations  a  year,  in  the  South  there  are 
])robal)ly  niorc^  generations,  while  at  th(>  northern  limit  of  the 
species  there  are  two  or  possibh'  threc>  generations,  as  breeding 
continues  until  after  killing  frosts.     As  with  other  small  insects,  it 


-^v 


Fk;.  392. — Peach  leaf  bearing  San  Jose  scales  along  veins. 


is  the  remarkable  power  of  reproduction  to  which  the  destructive- 
ness  of  the  pest  is  due.  Thus  it  has  been  estimated  that  at  Wash- 
ington, D.  C,  the  progeny  of  a  single  female  would  number 
3,210,080,400  by  fall,  if  all  were  to  survive.     It  is  not  surprising, 


Fig.  .393. — Adult  female  San  Jose  scale,  with  scale  removed  to  expose  the 
insect.     (After  Alwood.) 

therefore,  that  a  tree  wuth  but  a  few  scales  on  it  in  spring  will  be 
covered  by  them  and  the  fruit  unfit  for  market  in  the  fall,  and  that 
with  these  millions  of  little  Ijeaks  pumping  out  the  sap  and  poison- 
ing the  tissues  a  tree  soon  succumbs. 


542         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  pest  has  been  spread  mostly  by  being  transported  on 
nursery  trees.  Trees  infested  from  the  nursery  will  usually  have 
more  scales  on  the  lower  trunk,  from  which  they  will  spread  to 
the  limbs,  while  those  infested  from  neighboring  trees  will  have 
more  scales  on  the  young  wood.  Where  the  pest  is  abundant 
the  young  insects  are  undoubtedly  blown  from  tree  to  tree  by  the 


Fig.  394. — Young  larva  and  developing  San  Jose  scale  {Aspidiotus  perniciosus 
Comst.):  a,  ventral  view  of  larva,  showing  sucking  beak  and  setae  sepa- 
rated, with  enlarged  tarsal  claw  at  right;  b,  dorsal  view  of  same,  still 
more  contracted  and  with  the  first  waxy  filaments  ajjpearing;  c,  dorsal 
and  lateral  views  of  same,  somewhat  contracted,  illustrating  furthc 
development  of  wax  secretion ;  d,  later  stage  of  the  same  dorsal  and  lateral 
views,  showing  matting  of  wax  secretions  and  first  form  of  young  scale — 
all  greatly  enlarged.     (After  Howard  and  Marlatt,  U.  S.  Dept.  Agr.) 

wind,  or  tlu^y  may  be  carried  on  the  feet  of  birds  or  insects,  or 
brushed  off  and  carried  by  persons  or  teams  working  in  the  orchard. 
^  The  insect  has  been  found  on  a  long  list  of  plants,  but  on  many 
of  them  it  is  largely  accidental.  Injury  is  practically  confined 
to  plants  of  the  Rosacece,  which  family  includes  all  our  common 
deciduous    fruits.     Of  the    orchard   trees    peach,  pear,  Japanese 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS       543 


plum,  apple  and   quince   arc  most  injured    n  the  order  named; 
while  cherry  and  European  plum  are  less  injured. 

Control. — As  yet  no  spray  has  been  found  for  use  in  summer 
which  will  more  than  check  the  increase  of  the  pest  without 
injury  to  the  tree,  and  summer  spraying  is  resorted  to  only  when 


Fig.  395. — One  of  the  most  important  native  enemies  of  the  San  Jose  scale, 
a  Httle  black  ladybird-beetle  (Microweisea  misella):  a,  beetle;  6,  larva; 
c,  pupa;  d,  beetles,  larvse,  and  pupae,  among  scales — all  greatly  enlarged. 
(After  Marlatt,  U.  S.  Dept.  Agr.) 

winter  treatment  has  been  neglected  or  has  proven  inefficient. 
10  or  15  per  cent  kerosene  emulsion,  dilute  miscible  oils,  dilute 
lime-sulfur  mixture,  or  whale-oil  soap,  1  pound  to  4  or  5  gallons, 
may  be  used  for  summer  spraying. 

On  the  Pacific  Coast  trees  are  very  generally  fumigated  with 
hydrocyanic  acitl  gas  *   for  th's  and  other  scale  insects,  but  the 

*See  C.  W.  Woodworth,   Bulletins   122  and   152,  Cal.   Agr.  Exp.  Sta.; 
R.  S.  Woglum,  Bulletins  79  and  90,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


544         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

treatment  has  never  come  into  favor  in  the  East,  principally, 
perhaps,  because  of  the  larger  trees  and  the  more  scattered  nature 
of  the  fruit  'ndustry. 

Practically  the  only  methods  now  used  in  the  East  consist  in 
spraying  the  dormant  trees  with  washes  which  penetrate  the 
scales  and  destroy  the  insects.  This  may  be  done  more  effec- 
tively if  the  trees  are  pruned  and  headed  in  so  as  to  reduce  the 
wood  to  be  covered.  Rough  bark  should  be  scraped  off  so  that 
the  scales  beneath  may  be  reached.  Badly  infested  trees  should 
be  sprayed  in  the  the  early  winter  as  soon  as  they  have  hardened 
up  and  again  in  the  spring  just  as  the  buds  commence  to  swell.  The 
spring  spraying  will  suffice  for  trees  slightly  infested.  Every  bit  of 
bark  on  the  tree  must  be  thoroughly  wet,  so  none  will  escape. 
Lime-sulfur  mixture  seems  to  be  the  favorite  wash  for  winter 
spraying  at  present,  as  it  not  only  kills  the  scale,  but  aids  in  the 
control  of  many  fungous  diseases  (see  p.  50).  Miscible  oils  are 
also  extensively  used  and  have  a  certain  advantage  on  hairy 
apple  shoots  and  on  Ijadly  infested  trees,  as  they  arc  more  pene- 
trating and  spread  better.  Kerosene  or  crude  oil  emulsion  con- 
taining 20  to  25  per  cent  of  oil  was  the  first  remedy  to  be  used  and 
is  still  extensively  employed.  Wha'e-oil  soap,  at  the  rate  of  2 
pounds  to  the  gallon,  applied  hot,  is  effective,  but  is  too  expensive 
for  large  users.     (See  p.  50). 

The  Fruit-tree  Bark-beetle  * 

If  the  outer  Ijark  is  punctured  by  numerous  small  "  worm- 
holes  "  so  that  it  looks  as  if  it  had  been  struck  with  a  charge 
of  bird-shot,  it  indicates  the  presence  of  the  fruit-tree  bark-beetle 
or  some  nearly  related  species  (see  p.  653).  Usually  more  or 
less  gum  exudes  from  the  holes,  particularly  on  stone  fruits. 
Diseased  or  weak-growing  trees  are  most  subject  to  attack,  but 
occasionally  serious  damage  is  done  to  perfectly  healthy  trees, 
especially  when  young.  Injury  is  largely  due  to  allowing  dead 
and  dying  trees  to  stand  in  the  orchard,  thus  encouraging  the 

*  Scolytus  rugulosus  Ratz.  Family  Scolytidce.  See  F.  H.  Chittenden, 
Circular  29,  Division  of  Entomology,  U.  S.  Dcpt.  Agr. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


545 


breeding  of  the  post  in  them  and  its  spread  to  healthy  trees. 
"  Another  foim  of  injury  is  the  destruction  at  the  beginning  of 
spring  of  small  twigs,  together  with  the  leaves  which  they  bear. 
The  beetles  are  also  reported  to  destroy  leaves  by  boring  into  the 
base  of  the  ])uds  at  their  axils."  The  hou^  in  the  bark  are  caused 
by  the  exit  of  the  small  parent  beetles  and  by  their  subsequent 
entrance  to  deposit  eggs.  The  adult  beetle  is  about  one-tenth 
inch  long,  b}'  a  third  as  wide,  and  of  a  uniform  black  color,  except 
the  tips  of  the  wing-covers  and  parts  of  the  legs,  which  are  red. 
Life  History. — The  beetles  emerge  from  the  trees  in  April  and 
May  in  the  JMiddle  States.  The  female  burrows  through  the  bark, 
and  partly  in  it  and  partly  in  the  sap-wood  she  eats  out  a  vertical 


a  he  d 

Fig.  396, — The  fruit-tree  bark-beetle  (Scolytus  mgvlosus):    a,  b,  beetle;    c, 
pupa;  d,  larva — enlarged,      (.\fter  Chittenden,  U.  S.  Dept.  Agr.) 

gallery  or  brood  chamljer,  along  the  sides  of  which  at  short  inter- 
vals she  gnaws  out  little  pockets  in  which  she  places  her  eggs. 
The  larvie  hatching  from  these  eggs  excavate  little  side  galleries, 
which  branch  out  and  widen  as  the  larva?  increase  in  size  (Fig. 
397).  The  larvae  become  mature  in  about  three  weeks,  when  they 
form  cells  at  the  ends  of  their  burrows  and  transform  to  pupae, 
from  which  the  adult  beetles  emerge  about  a  week  later.  There 
are  probably  three  generations  a  year  in  the  Middle  States  accord- 
ing to  Dr.  Chittenden. 

Were  it  not  for  the  effective  work  of  parasitic  and  predaceous 
insects  which  prey  upon  it,  this  insect  would  be  a  most  serious 
pest.     One  of  the  most  valuable  of  these  is  a  little  chalcis-fly  * 


*  Chiropnchis  colon  Linn. 


546        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


of  which  Dr.  Chittenden  bred  92  specimens  from  72  of  the  develop- 
ing beetles,  and  we  have  frequently  had  twigs  in  which  practically 
all  of  the  developing  beetles  were  parasitized. 

Control.— The  most  important  point  in  the  control  of  this  and 
similar  j)ests  is  to  cut  out  and  destroy  all  dead  and  diseased  wood. 

Burn  all  prunings  and  trim- 
mings. Affected  trees  should  be 
liberally  fertilized  in  the  spring 
so  that  they  may  make  a  quick 
growth  and  better  withstand  the 
injur}'.  Repellant  washes  have 
been  advised  for  deterring  the 
beetles  from  ovipositing.  A 
thick  soap  wash  containing  a 
pint  of  crude  carbolic  acid  to  10 
gallons  may  be  used.  Professor 
Gossard  advises  whitewashing  the 
trees  in  early  spring,  again  in  mid- 
summer and  lastly  about  October 
1st,  adding  one-quarter  pound 
of  table  salt  or  some  Portland 
cement  to  make  it  more  adhe- 
sive. He  also  reports  killing  the 
beetles  in  their  burrows  with 
an  enuUsion  of  carbolineum. 
''Emulsif}^  by  dissolving  3  pounds 
of  naphtha  soap  in  3  gallons 
of  water  by  l)oiling.  While  hot, 
add  1  gallon  of  carbolineum 
(arvenarius)  and  agitate  as  for 
kerosene  emulsion  with  a  force 
pump.  Add  four  gallons  of 
water  for  use  and  apply  with  a  spray  pump.  Keep  face  and 
hands  protected  from  this  spray."  The  carbolineum  is  rather 
expensive,  however,  and  does  not  seem  to  be  much  more 
effective  than  the  whitewash. 


Fig.  397.— Work  of  the  fruit-tree 
bark-beetle  showing  the  main 
galleries,  the  side  or  larval  galler- 
ies, and  the  pupal  cells — slightly 
enlarged.     (After  Ratzeburg.) 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS       547 

The  Buffalo  Tree-hopper  * 

The  work  of  the  Buffalo  Tree-hopper  consists  of  a  series  of 
cuts  or  incisions  in  the  limbs  of  fruit  or  shade  trees,  made  by  the 
female  in  the  process  of  egg-laying,  which  result  in  very  character- 
istic wounds.  This  injury  is  somewhat  like  that  done  by  the 
periodical  cicada  or  by  tree  crickets,  but  the  scars    are    larger 


Fig.  398. — The  buffalo  tree-hopper  (Ceresa  bubalus  Fab.):  a,  a,  adult,  enlarged 
and  natural  size;  twig  of  apple  showing  recent  egg-punctures  at  6;  c, 
bark  reversed  with  eggs  in  position;  d,  single  row  of  eggs — enlarged; 
e,  wounds  of  two  or  three  years  standing  on  older  limbs.  (After  Mar- 
latt,  U.  S.  Dept.  Agr.) 

and  are  placed  irregularly.  When  badly  attacked  the  limbs  of 
small  trees  sometimes  become  so  scarred  that  they  are  badly 
stunted  or  may  be  killed.  The  parent  of  this  mischief  is  a  curious 
little  grass-green  insect,  about  three-eighths  inch  long,  whose 
pronotum  is  broadly  expanded  into  two  sharp  horns,  which  are 

*  Ceresa  bubalus  Fab.  Family  Membracidae.  See  C.  L.  Marlatt,  Circular 
23,  Div.  Ent.,  U.  S.  Dept.  Agr.,  and  H.  E.  Hodgkiss,  Tech.  Bulletin  17,  N.  Y. 
Agr.  Exp.  Sta.,  p.  92. 


548         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

fancied  to  be  like  those  of  the  buffalo,  as  indicated  by  the  conunon 
name  of  the  insect.  They  are  very  common,  frequenting  all 
sorts  of  rank-growing  vegetation,  appearing  in  midsummer,  and 
being  most  numerous  in  August  and  September. 

Life  History. — Egg-laying  is  commenced  in  August  and  is 
continued  until  killing  frosts.  The  eggs  are  laid  in  two  curved  slits, 
with  from  six  to  twelve  in  each,  as  shown  in  Fig.  398,  c,  d.  In 
making  these  slits  the  fenuile  cuts  the  bark  between  them  entirely 
loose,  so  that  the  intervening  wood  soon  dies,  possibly  to  prevent 

the    growth    of    the  wood    crushing  the 
i   I   ^  eggs.     A    large    scar    is     thus     formed 

JMB||^2^^M^  which     enlarges     with       each     season's 

"^^^^^Kf^^X^  growth,    and    finally    becomes    an  oval 

^^W^^'         ♦'.---^•r        shape    by     the     center     dropping     out. 
After     a      few      years     badly    infested 
limbs    become    very   rough,    are    easily 
Fig.  399.  —  Nymph  of        broken    by  the  wand  and    furnish    van- 
buffalo   tree-hopper—       ^age    points    for    the  attack  of  borers, 
enlarged.       (After        ^,  i,i,i  .      ■^T 

Hodgkiss.)  Ti^®    ^gg^   '^^^^^  *^®  ^®^*  ^^^y  o^' 

June.  Like  the  adults,  the  young 
nymphs  feed  on  all  sorts  of  succulent  vegetation,  seeming  to  prefer 
the  juicy  annual  jDlants  even  to  the  tender  terminals  of  trees, 
the  orchards  suffering  most  being  those  grown  up  in  weeds. 

Control. — By  keeping  young  orchards  well  cultivated  and  free 
from  weeds,  the  nymphs  will  have  no  food  in  early  summer  and 
will  starve  or  leave  for  better  feeding  grounds.  Patches  of  weeds 
near  young  orchards  should  also  be  destroyed.  When  trees  are 
badly  wounded  by  the  egg  punctures  th(\y  should  be  well  pruned 
and  the  primings  })urned  to  destroy  the  eggs. 

The  Periodical  Cicada  * 

"  There  is  probably  no  insect  that  has  attracted  more  general 
interest  and  attention  in  this  country  than  the  Periodical  Cicada, 
or  the   so-called   Seventeen-year   Locust.     The   earliest   settlers 

*^Cicada  septendecim  Linn.  Family  CicadidoB.  See  C.  L.  Marlatt,  Bulletin 
71,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  A.  D.  Hopkins,  Bulletin  68, 
W.  Va.  Agr.  Exp.  Sta. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS       549 


doubtless  associated  its  vast  noisy  swarms  with  the  devastating 
invasions  of  the  Migratory  Locust  of  the  East.  Hence  the  popular 
name  locust,  which  has  been  used  so  long  that  it  is  doul)tful  if  it 
will  ever  l^e  discarded  for  the  proper  name — Periodical  Cicada." 
They  are  quite  different  from  the  true  locusts,  or  grasshoj^pers, 
however,  for  the  latter  have  biting  mouth-parts  while  the  cicadas 
are  true  bugs  and  suck  the  j  uices  of  the  plant  through  a  tube-like 
beak.  Some  twenty-two  distinct  broods  of  the  cicada  have  been 
distinguished,  thirteen  of  which  appear  at  seventeen-year  intervals 
and  seven  of  them  appear  at  thirteen-yeai"  intei'vals,  the  former 


Fig.  400. — The  periodical  cicada  {Cicada  seplendecim  Linn.):  a,  adult;  b, 
young  nymph — enlarged;  c,  cast  skin  of  full  grown  nymph;  (/,  adult 
females  showing  ovipositor  at  b,  and  beak  at  a — natural  size.  (After 
Marlatt  and  Riley,  U.  S.  Dept.  Agr.) 

being  mostly  in  the  North  and  the  latter  mostly  in  the  South. 
Some  one  or  more  of  these  broods  appears  in  every  State  east  of 
the  Rockies  except  Maine,  Xew  Hampshire  and  Vermont.  Every 
year  there  is  a  brood  emerging  in  some  part  of  the  country,  and 
the  different  broods  have  been  carefully  mapped  so  that  their 
emergence  may  be   anticipated. 

Life  History. — The  adults  appear  in  immense  swarms  in  late 
May  or  early  June.  "  About  four  or  five  days  after  their  first 
appearance,"   says    Dr.   Hopkins,   "  the    males    begin  to    sing " 


550        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


filling  the  air  with  their  shrill  calls,  which  are  produced  by  two 
drum-like  membranes  on  the  under  surface  of  the  first  abdominal 
segment.  "  About  eight  or  ten  days  later  the  sexes  begin  to 
mate,  and  in  about  four  or  five  days  more  the  females  commence 
to  deposit  eggs.  Each  female  is  said  to  deposit  from  three  to 
five  hundred  eggs  in  numerous  ragged  punctui'cs  made  by  her 
powerful  ovipositor  in  the  twigs  of  shrubs  and  trees,  and  sometimes 
in  the  stems  of  herbaceous  plants.  These  hatch  in  about  six  or 
eight  weeks  from  the  time  they  are  deposited  and  the  young 
cicada  Jarva3  emerge  and  fall  to  the  groimd.     They  then  Inirrow 


Fig.  401. — Egg  mass  of  the  periodical  cicada:  a,  recent  puncture,  surface  view, 
h,  same,  with  surface  removed  to  show  arrangement  of  eggs;  c,  same, 
side  view;  d,  egg  cavity  with  eggs  removed,  and  showing  the  sculpture 
left  by  the  ovipositor — all  v^nlarged.     (After  Riley,  U.  S.  Dept.  Agr.) 

beneath  the  surface  and  enter  upon  their  long  menial  existence 
in  the  ground,  feeding  on  the  liquids  of  roots  and  possibly  sub- 
sisting on  such  nutriment  as  may  be  obtained  from  the  soil  itself. 
They  change  their  position  from  time  to  time,  and  may  rarely 
enter  the  earth  for  a  distance  of  eight  to  ten  feet  or  more,"  though 
usually  within  two  feet  of  the  surface.  "  By  the  twelfth  or 
thirteenth  year  the  larva  attains  its  full  growth  and  in  time  changes 
to  the  intermediate  or  pupa  stage.*     During  the  spring  of  the 

*  Dr.  Hopkins  and  other  writers  commonly  use  the  terms  larva  and  pupa 
in  describing  the  immature  stages  of  the  cicada,  but  there  seems  no  reason 
for  discarding  the  term  nymph  used  for  other  Hemiptera,  and  which  is  cer- 
tainly useful  in  distinguishing  the  immature  stages  of  insects  with  incomplete 
metamorphosis  from  those  with  complete  metamorphosis  which  have  a  true 
pupa. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS       551 

fifteenth  and  sixteenth  years  great  numl^ers  of  the  pupa?  may  be 
found  near  the  surface,  and  a  few  individuals  may  emerge  during 
May  and  June  of  the  sixteenth  year.  Earh-  in  April  of  the  seven- 
teenth year  the  pupa?  commence  to  make  preparations  to  emerge 
from  the  ground  by  excavating  burrows  or  exit  galleries  to  the 
surface.  These  exits  are  completed  by  the  last  of  April.  Ordi- 
narily they  extend  only  to  the  surface,  and  are  kept  open  from  a 
depth  of  a  few  inches  to  a  foot  or  more.  In  some  soils  these 
exit  holes  are  extended  four  or  five  inches  above  the  surface  by 
means  of  clay  carried  up  from  the  subsoil,  and  are  called  cicada 


Fig.  402. — Pupal  galleries  or  chimneys  of  liie  periodical  cicada:  a,  front 
view;  e,  orifice;  h,  section  of  a;  c,  pupa  awaiting  time  of  change;  d, 
pupa  ready  to  transform — reduced  in  size.     (After  Riley,  U.S.  Dept.  Agr.) 

chimneys.  The  pupae  come  from  the  ground  in  the  evening  and  at 
night,  usually  between  sundown  and  ten  o'clock,  and  proceed  to 
the  nearest  upright  object,  which  may  be  a  tree,  the  side  of  a 
building,  fence,  or  weed  stem — anything,  in  fact,  upon  wh';ch  they 
can  climb  and  expose  their  bodies  to  the  action  of  the  open  air. 
In  about  an  hour  after  emerging  the  skin  on  the  back  splits  open 
and  the  adult  insect  works  its  way  out  (Fig.  403).  The  wings, 
which  are  short  and  soft  at  first,  rapidly  develop;  the  bod}-, 
wings  and  legs  harden,  and  by  the  following  day  the  adult  is  ready 
to  take  flight  and  enter  upon  its  short  aerial  life,  limited  to  about 
thirty  days.     During  this  short  period  they  feed  but  little,  if  at 


552         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


all,  the  males  devoting  their  time  during  the  day  to  flying  about 
and  making  a  noise,  while  the  voiceless  females  busy  the^iselves 
depositing  eggs.  "  If  the  young  n}-mphs  do  any  injury  to  the 
roots  of  trees  or  plants,  it  is  very  rarely  perceptible.  The  adult 
females,  however,  are  capable  of  causing  serious  injury  to  young 
fruit  trees  in  orchards  and  nurseries  by  the  numerous  punctures  in 
the  twigs,  limbs  and  main  stems  made  by  them  in  the  act  of 


Fig.  403. — The  full-grown  nymphs  of  the  periodical  cicada  in  different  stages 
of  molting  and  the  newly  emerged  adults  with  body  and  wings  still  soft 
and  white. 

ovipositing.  The  egg  puncture  makes  an  ugly  wound,  beyond 
which  the  twig  dies,  and  the  foliage  of  large  trees  on  which 
hundreds  of  cicadas  have  oviposited  turns  brown,  as  if  the  tree 
had  been  scorched  by  fire.  On  young  trees  this  results  in  destroy- 
ing the  growth  of  a  year  or  two  and  misshaping  the  tree,  and  the 
scars  which  remain  later  furnish  points  of  attack  for  borers  and 
the  woolly  apple-aphis. 


SOME  INSECTS  INJURiOUS  TO  ORCHARD  FRUITS        553 

Just  before  the  cicadas  leave  the  ground  they  are  attacked 
by  hogs  and  also  by  disease.  Upon  leaving  the  ground  they  are 
at  once  assailed  by  a  host  of  predaccous  insects  and  various  animals. 
One  of  the  most  valual)le  insect  enemies  is  a  large  wasp  (Sphecius 
speciosus  Dru.),  which  nui}-  often  be  seen  bearing  the  adults 
to  its  burrow,  where  the}-  furnish  food  for  her  young.  The  Eng- 
lish sparrow  is  remarkably  fond  of  the  adults  and  is  the  most 
valuable  factor  in  exterminating  them  in  cities  and  towns.  It 
has  been  noticed  that  cicadas  are  much  more  likely  to  emerge 
from  newly  cleared  land,  and  with  the  removal  of  the  forests  and 
cultivation  of  the  land  they  are  undoubtedly  becoming  more 
scarce. 

Control. — There  is  no  means  of  destroying  the  adults,  Init  many 
of  the  pupse  may  be  destroyed  by  allowing  hogs  to  run  on  land 
known  to  be  infested  during  April  and  May  of  the  year  they 
emerge,  where  it  is  feasible  to  do  so.  Injury  to  3'oung  orchards 
may  be  avoided  by  not  jDlanting  during  the  year  or  two  previous 
to  the  emergence  of  a  brood  in  the  particular  locality.  Budding 
and  grafting  should  also  be  avoided  during  the  previous  spring. 
Orchards  should  not  be  pruned  the  year  before  a  cicada-year, 
so  that  there  may  be  plenty  of  young  wood  in  which  they  may 
oviposit  and  which  may  then  be  removed  wdthout  injury  to  the 
tree.  Evidently  a  knowledge  of  the  time  of  appearance  of  each 
brood  in  different  sections  is  of  great  importance  and  may  be 
secured  from  the  maps  published  (see  Marlatt,  I.e.).  After  all 
the  eggs  are  laid  the  affected  twigs  should  be  pruned  off  in  July 
and  burned  l)efore  the  eggs  have  hatched. 

The  Fall  Webworm  * 

The  conmion  fall  wel)worm  is  so  called  because  in  the  North, 
where  there  is  but  a  single  generation,  its  webs  are  abundant  in 
August  and  September,  in  contrast  to  those  of  the  tent  cater- 
pillar, with  which  they  are  often  confused,  which  are  found  in 
the  spring.  The  wings  of  the  adult  moths  expand  from  one  to 
*  Hyphantria  cunea  Dru.     P^imily  Arctiidce. 


554      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

Ij  inches,  and  are  either  a  pure  milk-white,  or  more  or  less  spotted 
with  black,  the  number  of  spots  being  exceedingly  variable.  The 
full  grown  caterpillars  are  about  an  inch  long,  covered  with  long 
black  and  white  hairs  which  project  from  numerous  black  tubercles. 


Fig. 404. —  The  fall  webworm  (Hyphantria  cunea  Dru.):  «,  light  form  of  full- 
grown  larva;  b,  dark  form  of  same;  c,  pupa;  d,  spotted  form  of  moth — 
all  slightly  enlarged.     (After  Howard,  U.  S.  Dept.  Agr.) 


They  are  also  quite  variable  in  color,  some  being  uniformly  }'ellow- 
ish  with  black  and  yellow  tubercles,  while  others  have  a  dark 
stripe  down  the  back  and  are  almost  black. 

Life  History. — In  the  North  the  moths  emerge  late  in  June  and 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        555 


Fig.  405. — Web  of  the  full  webworm  on  apple,  showing  enclosed  foliage  and 
larvse  feeding  within. 


556  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

in  Jul}^,  and  lay  the  eggs  late  in  July.  The  eggs  are  deposited 
on  the  leaves  in  pale  yellowish-green  patches  of  400  to  500,  often 
covered  with  whitish  down  from  the  body  of  the  female,  and 
hatch  in  about  ten  days.  The  young  larvae  are  pale  yellowish 
with  brown  markings  and  appear  to  be  almost  all  head  and  hair. 
They  at  once  spin  a  web  over  the  foliage  on  which  they  are  feeding, 
those  from  one  egg  mass  feeding  together  and  enlarging  the  web 
as  necessary.  In  the  North  the  webs  are  usually  noticed  in  early 
August  and   are  started  at  the  tips  of  the  limbs.     Within  them 


Fig.  406. — Meteorus  hyphantria;,  a  common  parasite  of  the  fall  webworm; 
a,  adult  female;  b,  empty  cocoon  showing  cap  and  suspending  thread 
— enlarged.     (After  Riley,  U.  S.  Dept.  Agr.) 

the  surfaces  of  the  leaves  are  eaten  off  until  they  are  left  dry  and 
brown.  When  all  the  foliage  on  a  limb  has  been  consumed,  the 
caterpillars  leave  the  web,  enclosing  the  dead  leaves,  and  form  a 
new  web  on  a  fresh  branch,  and  thus  the  tree  soon  becomes  covered 
with  unsightly  webs,  which  arc  often  mingled  so  that  the  whole 
tree  is  webbed  over.  The  web  is  easily  distinguished  fi'om  that 
of  the  tent  caterpillar,  as  it  is  found  later,  and  the  tent  caterpillar 
makes  a  relatively  small  web  in  the  fork  of  a  limb  and  never 
encloses  foliage  in  it.     The  caterpillars  become  full  grown  in  a 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        557 

month  to  six  weeks,  and  then  find  seckided  places  under  the  bark 
or  in  a  hollow  of  the  tree,  in  the  rubbish  at  its  base,  or  in  a  fence 
cornel',  or  sometimes  just  under  the  surface  soil,  and  there  spin 
fhms}'  silken  cocoons  witli  whicli  they  mingle  their  own  hairs. 
They  then  transform  to  small  brown  pupa?  about  one-half  inch 
long,  in  which  stage  the  winter  is  passed.  In  the  Middle  States 
and  further  south  there  are  two  generations,  the  moths  appearing 
in  April. and  May  and  la.}'ing  eggs  in  late  Ma}'  and  early  June,  the 
caterpillars  from  which  l^ecome  full  grown  ]:)y  mid-July.  The 
second  generation  of  caterpillai's  appear  in  late  August  and  Sep- 
temlier  at  a])out  the  same  season  as  further  north,  and  their 
pupa^  hiljernate. 

^^'ere  it  not  for  their  parasitic  enemies  these  caterpillars  would 
be  much  more  of  a  pest,  and  it  is  wlien  the  parasites  become  scarce 
that  injur}'  results.  One  of  their  most  common  and  effective  ene- 
mies is  a  little  Braconid  fly,*  whose  small  brown  cocoon  (Fig. 
406)  is  often  found  suspended  from  a  twig  or  leaf.  Many 
caterpillars  are  also  killed  I^}-  various  predaceous  bugs,  and  fre- 
quently they  are  killed  off  by  fungous  disease. 

The  fall  webworm  is  a  common  pest  of  all  orchard  trees,  and 
frequently  extends  its  injuries  to  shade  trees.  The  larva?  are  not 
uncommon  on  cabbage,  beets  and  a  long  list  of  garden  crops. 
According  to  Dr.  H.  G.  Dyar  this  species  is  confined  to  the  South 
Atlantic  States,  but  it  has  been  confused  with  another  species 
(Hijphantria  textor  Harris)  l)y  practically  everyone,  and  it  is  still 
a  question  as  to  whether  the  two  species  are  really  distinct  and 
if  so  how  they  are  to  be  distinguished.  If  the  latter  form  be  a 
distinct  species,  it  occurs  throughout  the  United  States  and  has 
the  same  habits. 

Control. — The  insect  is  readily  controlled  by  spraying  with  any 
of  the  arsenicals  when  the  work  of  the  young  larvae  is  first  noticed. 
\Miere  orchards  are  sprayed  for  the  codling  moth  there  will  be 
little  trouble  with  the  first  generation,  and  fruit-growers  will  do 
well  to  make  it  a  practice  to  spray  in  August  where  they  are 
troubled  with  this  and  other  leaf-eating  caterpillars. 
*  Meteorus  hyphantrlce  Riley. 


558        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


The  Brown- tail  Moth  * 

Althougli  the  Brown-tail  Moth  has  bocomo  injurious  only  in 
Massachusetts,  New  Hampshire  and  Maine,  it  will  be  surprising 
if  it  tloes  not  become  generally  distributed,  for  during  the  past 
three  years  its  nests  have  been  imported  on  pear  seedlings 
from  France  by  nurseries  in  all  parts  of  the  United  States 
and  southern  Canada,  and  possibly  some  have  escaped  even  the 
most   vigilant   inspectors.      It   has  long   been  a  serious  pest  in 

parts  of  central  and  western  Europe, 
whence  it  was  introduced  into 
Massachusetts  about  1S90,  l)ut  did 
not  attract  attention  until  1897. 
The  female  moth  is  pure  white 
except  the  tip  of  the  a])domen, 
which  is  golden  brown  and  forms 
a  lai'ge  tuft  or  Ijrush,  which  gives 
the  insect  its  name.  The  wings 
of  the  female  expand  Ih  inches, 
the  males  being  slightly  smaller, 
and  1)ear  one  or  two  streaks  of 
brown  on  the  under  sides.  The 
full-gi'own  caterpillar  is  1^  inches 
long,  dark  brown,  marked  with  a 
white  dash  on  the  side  of  each 
segment.  The  body  is  dark  l^rovni 
or  blackish,  well  marked  with 
patches  of  orange  and  covered  with 
numerous  tubercles  bearing  long 
barljed  hairs.  On  the  centre  of  the  fifth  and  sixth  alxlominal 
segments  are  small  retractile  red  tubercles.  The  tubercles 
along  the  back  and  sid(>s  are  thickly  covered  with  short  brown 
hairs  which  give  them  a  velvety  appearance.  These  micro- 
scopic hairs  are  liarbed  and  are  the  nettling  hairs  which,  when 

*  Euproctis  chryscrrhoea  Linn.  Family  Liparidce.  See  L.  O.  Howard, 
Farmers'  Bulletin  264,  U.  S.  Dept.  Agr.;  E.  D.  Sanderson,  Bulletin  136,  N.  H. 
Agr.  Exi3.  Sta. 


Fig.  407. — Winter  web  of  the 
brown-tail  moth — one-half 
natural  size. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        559 

they  alight  on  the  skin,  produce  a  dermatitis  much  Uke  that  caused 
by  poison  ivy.     As  the  cast  skins  are  carried  here  and  there  by  the 


Fig.  408. — "Winter  web  of  the  brown-tail  moth  cut  open  to  .show  cells  within. 

wind  and  the  young  caterpiUars  di-op  from  the  trees,  people 
are  frecpently  ])adl}'  poisoned  where  the  pest  becomes  abundant, 
so  that  it  is  a  serious  public  nuisance  as  well  as  a  defoliator  of 


Fig.  409. — Winter  web  of  the  bro'.\-n-tail  moth  bearing  j^oung  larvae  which 
have  emerged  before  the  foliage  has  ai)i)eared  and  are  feeding  on  the 
dead  leaves  of  the  rest — two-tliirds  natural  size. 

fruit  and  shade  trees.     The  caterpillars  prefer  fruit  trees,  pear, 
wild  cherry,  and  apple  being  most  relished,  l)ut  become  abundant 


560       INSECT  PESTS  OF    FARM,  GARDEN  AND  ORCHARD 

on  almost   all  the  common    shade  trees,  except  the  evergreens, 
and  particularly  on  oak. 

Life  History. — The  moths  emerge  in  midsiinmier.     They  are 


Fig.  410. — Full  grown  larvic  of  the  brown-tail  moth — natural  size. 

strong  fliers  and  are  readily  carried  by  the  wind  for  many  miles. 
They  are  attracted  to  lights  in  great  numbers,  so  that  they  are 


Fig.  411. — A  mass  of  cofoons  of  the  brown-tail  moth  attaolioct  to  foliage. 

more  abundant  in  cities  and  villages.     Late  in  July  the  eggs  are 
laid  on  the  terminal  leaves,  300  or  400  being  laid  in  an  elongate 


SOiME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        501 


mass  and  fov^crcd  with  brown  hairs  from  the  tip  of  the  female's 
abdomen.  They  hatch  in  about  thixH'  weeks  and  the  young  hirvic 
feed  on  the  surface  of  the  leaves,  leaving  only  the  brown  skeletons, 
so  that  badly  infested  trees  turn  l)rowii  in  early  fall.  The  cater- 
pillars hatching  from  an  egg  mass  feed  together  on  adjoining 
leaves,  which  they  soon  commence 
to  draw  tog(^ther  with  silken 
threads,  and  by  the  first  frosts  they 
have  spun  them  into  a  tough 
web.  This  is  attached  to  the 
twig  l)}-  the  old  leaf  stems,  which 
are  bound  to  it  by  silk.  The 
web    looks    like    a  couple  of    dead 


Fig.  412.— The  brow-n-tail  moth  (Eu- 
■prodis  chrysorrhoea  Linn.):  male  above, 
female  below — natural  size. 


Fig.  413. — Brown-tail  moths 
assembled  on  electric-light 
pole,  Maiden,  Mass.,  July 
12,  1905.    (After  Kirkland.") 


leaves  from  a  distance,  but  the  leaves  are  merely  the  outer  covering, 
and  if  the  silk  web  be  torn  open,  there  will  be  found  numerous 
small  pellets  of  silk  each  enclosing  from  three  to  twelve  of  the  little 


562        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

partly  grown  caterpillars.  The  caterpillars  emerge  just  as  the  buds 
burst  in  the  spring  and  feed  on  the  expanding  foliage.  Where 
■abundant  they  soon  strip  a  tree,  for  each  of  the  nests  harbors 
400  or  500  little  caterpillars.  In  five  or  six  weeks  they  have 
become  full  5'rown  and  spin  thin  cocoons  of  white  silk  among 


w 


r 


Fig.  414. — Egg  masses  of  the  brown-tail  moth — natural  size;    caterpillars 
hatching  from  the  mass  on  leaf  at  left. 


the  leaves,  in  which  they  transform  to  dark-lirown  pupa^.     About 
three  weeks  later  the  moths  emerge. 

Several  native  parasites  and  predaceous  bugs  prey  upon  the 
caterpillars,  but  do  not  seem  to  materially  reduce  their  numbers. 
In  Europe  there  are  several  parasites  which  prey  on  all  stages 
of  the  insect  and  which  the  State  of  Massachusetts  with  the 
cooperation  of  the  U.  S.  Bureau  of  Entomology  is  introducing 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        563 


in  hope  that  they  may  ultimately  l)e  as  effective  in  this  country 
against  both  the  brown-tail  and  gipsy  moths.     The  most  effective 
natural  check  of  the  brown-tail  caterpillar  is  a  fungous  disease 
which    often     completely    de- 
stroys large  colonies,  both  in 
the  spring  and  fall. 

Control. — On  fruit  and  shade 
trees  the  winter  nests  may 
be  pruned  off  and  burned  in 
winter,  thus  preventing  any 
injury  the  next  spring,  but 
this  is  impracticable  on  forest 
trees,  which  as  a  rule  are  not 
seriously  injured.  The  re- 
peated pruning  often  injures 
the  trees,  as  it  is  d  fficult 
to  cut  all  the  nests  without 
removing  more  of  the  new 
growth  than  is  desirable.  It 
is  better,  therefore,  to  spray 
the  trees  with  arsenate  of  lead,  4  pounds  to  the  barrel,  as  soon 
as  the  eggs  hatch  in  late  summer,  and  thus  destroy  the  young 
larvse  before  they  have  spun  their  winter  webs. 


Fig.  415. — Young  caterpillars  of  the 
brown-tail  moth  skeletonizing  an 
apple  leaf  in  late  summer. 


The  Gipsy  Moth  * 

History. — The  Gipsy  Moth  has  been  known  as  a  serious  insect 
pest  in  Europe  from  the  time  of  the  earliest  naturalists,  the  first 
authentic  record  being  in  1662.  It  extends  throughout  the 
continent  of  Europe,  over  much  of  Asia  and  into  Northern  Africa, 
but  is  chiefly  injurious   in  central   and  eastern  Europe.     It  fre- 

*  Porthelria  dispar  Linn.  Family  Lipnridoe.  See  Forbush  and  Femald, 
"The  Gypsy  Moth,"  Mass.  State  Board  of  Agr.  (1892);  L.  O.  Howard, 
Farmers'  Bulletin  275,  U.  S.  Dept.  Agr.;  Annual  Reports  of  the  Mass.  Super- 
intendent for  the  Suppression  of  the  Gypsy  and  Brown- tail  Moths;  E.  D. 
Sanderson,  Bulletin  136,  N.  H.  Agr.  Exp.  Sta.;  Rogers  and  Burgess,  Bulletin 
87,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  containing  bibliography. 


564  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

qiiently  docs  serious  injury  there  by  defoliating  large  areas  of 
forest  and  more  frequently  fruit  and  shade  trees,  but  its  ravages 
cease  in  two  or  three  seasons,  not  to  occur  again  for  several  years, 
like  those  of  many  of  our  native  insects,  such  as  the  forest  tent 
caterpillar  and  tussock  moth.  In  ISGS  the  insect  was  brought 
to  this  country  by  Professor  Leopold  Trouvelot  at  Medford,  Mass., 
in  his  experiments  in  silk  producing.  Escaping  from  him  into  the 
neighboring  ^^■oodland,  the  insect  increased  gradually  for  several 
years  before  being  noticed,  but  in  1890  had  become  such  a  serious 


Fig.  416. — Gipsy  moth  caterpillars — natural  size.     (After  W,  E.  Britton.) 


pest  throughout  this  and  neighboring  towns  that  the  State  of  Massa- 
chusetts commenced  the  arduous  task  of  its  extermination.  At  this 
time  the  insect  occurred  in  some  twenty  towns.  For  the  next 
ten  years  it  was  successfully  combated  by  the  Massachusetts 
authorities,  and  in  1898  it  had  spread  to  but  three  towns  not 
infested  in  1890  and  in  many  places  it  had  apparently  been  exter- 
minated. So  slight  was  the  injury  that  legislative  appropriations 
were  discontinued  for  four  A'ears,  during  which  lime  the  moth 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS       505 

spread  over  four  times  the  area  previously  occupied  antl  became 
so  abundant  that  State  action  was  again  necessary.  From  1905 
to  1910  it  spread  throughout  eastern  Massachusetts  and  southern 
New  Hampshire  and  Maine,  and  was  found  in  two  or  three  local- 
ities in  Connecticut.  Appropriations  for  its  control  have  been 
increased  until  now  the  State  of  Massachusetts  and  the  Federal 
Government   are  each  appropriating  $300,000  per  annum    and 


Fig.  417. — The  gipsy  moth  (Porthetria  dispar  Linn.):    male  above;    female 
below — natural  size.     (After  Forbush  and  Fernald.) 


the  total  cost  of  combating  it  in  New  England  must  be  considerably 
over  a  million  dollars  per  year.  As  it  is  gradually  spreading, 
there  seems  every  reason  to  fear  that  it  may  ultimately  invade 
other  States. 

Life  History  and  Description. — The  eggs  are  laid  in  July  and 
August,  in  a  mass  of  400  to  500,  covered  with  yellowish  hairs 
from  the  body  of  the  female.     The  mass  is  an  irregular  oval 


566        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

shape  li  by  f  inches,  as  shown  natural  size  in  the  figure,  and  is 
deposited  on  the  bark  of  trees,  but  where  abundant,  on  fences, 
stones,  buildings,  etc.  The  eggs  hatch  about  May  1,  and  each 
mass  yields  a  swarm  of  young  caterpillars,  the  bulk  of  which 
become  full  grown  by  midsummer.  The  mature  caterpillar  has  a 
dusky  or  sooty-colored  body.  Along  the  back  is  a  double  row 
of  five  pairs  of  blue  spots,  followed  by  a  row  of  six  pairs  of  red 
spots,  which  readily  distinguish  this  from  any  other  common 


Fig.  418.— Egg  mass  of  the 
gipsy  moth  on  a  bit  of 
bark— natural  size. 


Fig.  419. — Pupa*  of  the  gipsy 
moth,  male  and  female — nat- 
ural size. 


caterpillar.  The  full-grown  caterpillar  is  al30ut  3  inches  long. 
Sometime  in  July  or  early  August  it  spins  a  few  threads  of  silk 
as  a  support,  sheds  its  skin  and  changes  into  a  pupa,  some- 
times enclosed  in  a  thin  cocoon,  but  often  hanging  pendant  from 
its  attachment.  Characteristic  light  reddish  hairs  are  scattered 
over  the  pupa  The  pupal  stage  lasts  from  ten  days  to  two  weeks, 
when  the  adult  emerges.  The  moths  emerge  from  the  m'ddle 
of  July  to  late  August.  The  male  is  brownish-yellow,  varying 
to  greenish-])rown  in  color,  the  wings  being  marked  with  darker 
,  stripes,  has  a  slender  body  and  the  wings  expand  about  Ih  inches. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS 


56/ 


It  flies  by  day  with  a  pofuliar  zig-zag  fliglit.  The  female  moth 
is  nearly  white  with  numerous  small  black  markings,  is  heavy- 
bodied  and  sluggish.  The  wings  expand  about  2  inches,  but 
fortunately  the  female  is  unable  to  use  them  for  flight.  Were  it 
not  for  this  the  spread  of  the  pest  would  have  been  much  more 
rapid.  After  mating  the  moths  live  but  a  short  time  and  do  no 
damage  themselves. 

The  pest  is  spread  mostly  in  the  caterpillar  stage.     The  young 


^-     ■     ■ 

.      -^ji^   ■'••?•■ "-;.-:. v;i: ■:"./"       -;' 

► 

ki 

R^  ■  -it.;^  ■  i  '^^uSwC  <i.  J6f«-  .^^Si^^  ■ 

^L  . 

\-  ■' 

"#'-t:.^|iP 

^    ^W«vr^if-if 

C."*^         .^'         ^         "'"         -'                                                                                                                     ^ 

fel 

SiiMMlJiilitlSlil 

Lriii^M^'^w* 

''••4b^^^^^^^^^| 

inqfi-^ri 

'     '"  'L 

1 

'  "^^^fstHSr^^^ 

^5 

Fig.  420. — Woodland  killed  by  being  stripped  by  the  gipsy  moth  caterpillars. 
Arlington,  Mass,  1905. 


caterpillars  drop  down  on  fine  silken  threads  and  may  alight  on 
vehicles  which  transport  them  to  non-infested  areas,  AYhen  just 
hatched,  the  caterpillars  have  very  long  hairs,  slightly  expanded 
at  the  base,  and  these,  with  the  silk  which  they  spin  out,  serve 
to  buoy  them  up  in  the  air  so  that  they  may  be  carried  for  a 
considerable  distance  by  a  strong  wind.  Where  they  occur  in 
myriads  on  high  trees,  it  seems  quite  probable  that  the  little 


568        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Fig.  421.— Egg  masses  of  the  gipsy  moth  on  the  trunk  of  an  apple  tree. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        569 

caterpillars  may  be  carried  by  the  wind  for  considerable  distances, 
and  that  this  is  one  of  the  chief  means  of  spread.  The  egg 
masses  may  also  be  transported  on  merchandise  or  l)oxing,  and  the 
pest  has  undoubtedly  become  established  in  several  localities  in 
this  way.  A  few  cases  of  importation  on  nursery  stock  have  been 
known. 

The  caterpillars  will  attack  any  of  the  fruit,  shade  or  wood- 
land trees,  and  where  they  become  excessively  alnmdant  will 
destroy  all  green  vegetation  of  almost  any  kind.  It  is  essentially 
a  pest  of  forest  trees,  but  where  it  occurs  it  defoliates  all  of  the 
common  fruit  trees.  Coniferous  trees  are  killed  after  being  once 
stripped  of  their  foliage,  and  deciduous  trees  usually  die  after  four 
or  five  defoliations.  Recent  experiments  show  that  the  young 
caterpillars  when  they  hatch  from  the  eggs  are  unable  to  feed  on 
conifers,  so  that  growths  of  soft  wood  may  be  protected  l^y  keeping 
all  hard- wood  trees  cut  out. 

Control. — In  the  orchard  the  gypsy  moth  is  readily  controlled 
by  painting  the  egg  masses  with  creosote  in  winter  and  by  spraying 
the  trees  with  arsenate  of  lead,  5  pounds  per  barrel,  just  as  the 
eggs  are  hatching  in  the  spring.  Where  this  is  practiced  there 
is  very  little  trouble  in  controlling  it  in  orchards.  Upon  shade 
and  forest  trees  the  problem  is  much  more  difficult  and  the  reader 
should  consult  the  authors  cited  (footnote  p.  563)  as  to  the  best 
means  and  apparatus.  Although  the  pest  is  still  confined  to 
New  England,  it  is  such  a  serious  one  and  there  is  so  much  danger 
of'  its  spread  elsewhere,  that  fruit-growxrs  should  be  on  their 
guard  against  it  and  should  submit  suspected  specimens  to  the 
nearest  entomologist.  Should  it  be  found  in  any  other  States, 
no  expense  should  be  spared  to  absolutely  exterminate  it  before 
it  may  become  established. 


570        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


Canker  Worms  * 

Since  the  early  colonial 
days  Canker  Worms  have 
been  among  the  best-known 
insect  pests  of  the  apple 
orchard,  but  they  are 
general  feeders  and  attack  several  orchard 
and  shade  trees.  According  to  Dr.  W.  E. 
Britton  they  "  seem  to  have  a  preference 
for  the  foliage  of  apple,  elm,  chestnut,  pear, 
oak,  hickory,  box-elder,  and  maple,  in  about 
the  order  named,"  and  cherry  and  plum 
are  I'ecorded  by  others.  The  canker  worms 
are  among  the  most  common  of  the  "  loopers  " 
or  ''  measuring  worms,"  and  are  the  larvae 
of  two  nearly  related  species  of  moths,  very 
similar  in  both  appeai'ance  and  habits.  The 
larvae  defoliate  the  trees  in  early  spring, 
particularly  in  old  sod  orchards  which  have 
not  been  cultivated  or  sprayed. 

The  Spring  Canker  Worm  f 

This  species  is  so  called  from  the  fact  that 
its  eggs  are  laid  in  the  early  spring  instead  of 
in  the  fall,  as  are  those  of  the  other  species. 
It  occurs  from  Maine  to  Iowa  and  southward 
to  Texas,  and  in  Colorado  and  California,  but 
has  not  been  rep  rted  on  the  Atlantic  Coast 
south  of  New  Jersey  according  to  Coc][uillet.    It 


*  Family  Geometridce.  See  D.  W.  Coquillet,  Circular 
9,  Div.  Ent.,  U.  S.  Dept.  Agr.;  W.  E.  Britton,  Bien- 
nial Report  Conn.,  Agr.  Exp.  Sta.,  1907-08,  p.  777; 
A.  L.  Quaintance,  Bulletin  68,  Part  II,  Bureau  of 
Entomology,  U.  S.  Dept.  Agr. 

t  Paleacrita  vernata  Peck.     Family  Geometridce. 


Fig.  422.— Canker 
worms  dropping 
from  foliage  in 
characteristic  at- 
titudes. (After 
Bailey.) 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        571 


seems  to  be  particularly  injurious  in  the  Mississippi  Valley.  The 
full-grown  caterpillar  is  from  three-quarters  to  one  inch  long, 
slender,  and  cylindrical,    and    has    but    one    pair  of  prolegs  on 


Fig.  423.  —  The  spring  canker  worm 
(Paleacrita  vernata) :  a,  male  moth ;  b, 
female  moth  —  both  natural  size;  r, 
joints  of  female  antenna;  d,  joint  of 
female  abdomen;  e,  ovipositor  —  en- 
larged.    (After  Riley.) 


Fig.  424. — The  spring  can- 
ker worm  (Paleacrita  ver- 
nata): a,  larva — natural 
size;  b,  eggs — natural  size 
and  enlarged;  c,  side  view 
of  segment  of  larva;  d, 
dorsal  view  of  same  — 
both  enlarged.  (From 
Riley.) 


the  middle  of  the  abdomen.  The  color  varies  from  ash-gray 
to  green  or  yellow,  but  the  predominating  color  is  dark  greenish- 
olive  or  blackish,  marked  with  narrow  pale  lines  down  the  back 


Fig.  425. — The  female  moths  of  the  spring  cankerworm — twice  natural  size, 
and  pupse — three  times  natural  size.     (.After  Quaintance,  U.  S.  Dept.  Agr.) 

and  a  whitish  stripe  along  each  side.  The  wings  of  the  male  moths 
expand  an  inch,  and  are  semi-transparent,  brownish-gray,  with 
three   rather   indistinct   dark   lines  across  the  fore-wings.      The 


572        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

females  are  wingless  and  at  the  first  glance  look  much  more  like 
spiders  than  moths.  They  are  about  one-third  inch  long,  of  a  dull 
brown  or  grayish  color  with  a  dark  l^rown  stripe  down  the  middle 
of  the  back. 

Life  History. — The  moths  emerge  from  the  pup^c  in  the  ground 
in  March  and  April  and  the  females  climb  up  the  trunks  of  the 
trees,  where  they  place  their  eggs  in  irregular  masses  of  about 
fifty,  under  loose  scales  of  hsa'k,  in  cracks  in  the  Ijark,  in  crotches 
of  limbs,  etc.  The  individual  eggs  are  yellowish-green,  turning 
quite  dark  just  before  the  larvie  hatch,  of  an  oval  shape,  and 
about   one-thirty-fifth    inch    long.     The   eggs   hatch    in    about   a 


Fig.  426. — Eggs  of  spring  canker  worm — twice  natural  size.     (After  W.  E. 

Britton.) 

month  and  the  young  caterpillars  commence  to  feed  on  the  leaves 
just  as  they  are  expanding,  at  first  eating  small  holes  through 
them,  but  later  devouring  all  but  the  midribs.  The  3'oung  cater- 
pillars have  a  habit  of  dropping  from  the  trees  and  hanging 
suspended  on  strands  of  silk.  In  four  or  five  weeks  they  have 
become  full  grown  and  enter  the  soil  to  a  depth  of  2  to  5  inches, 
where  they  hollow  out  earthen  cells,  which  they  line  with  a  little 
silk  and  in  them  change  to  pupic,  in  which  stage  the  summer  and 
winter  is  passed.  The  pupa  is  nearly  one-third  inch  long,  light 
brown  in  color,  somewhat  pitted,  and  the  male  pupa  bears  a 
simple  spine  at  the  tip  of  the  alxlomen. 

The  Fall  Canker  Worm  * 

The  Fall  Canker  Worm  seems  to  be  the  more  common  form  in 
New  England  according  to  Dr.  Britton  and  is  a  more  northern 
species    according    to    Coquillet,    occurriiig    through    the  North- 

*  Alsophila  pometuria  Harris.     Family  Geomctridce. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        573 

Central  States  and  in  Colorado  and  northern  California.  As  its 
name  indicates,  it  differs  in  life  history  in  that  the  moths  emerge 
in  November  and  Decendjer,  "  often  occiii-rin<i-  in  great  numbers 
on  foggy  days  during  a  thaw  after  the  ground  has  been  frozen." 
They  are  most  numerous  about  tht  middle  of  November  in  Connec- 
ticut, although  Dr.  Brittdn  states  that  when  the  ground  freezes 


Fic.  427. — The  fall  canker  worm  {Ahophila  pometaria):  a,  male  moth; 
b,  female — natural  size;  c,  joints  of  female  antenna;  d,  joint  of  female 
abdomen — enlarged.     (From  Riley.) 

in  early  fall  and  does  not  thaw,  many-  of  the  adults  do  not  emerge 
until  March,  when  the  life  history  would  be  identical  with  the 
last  species.  The  eggs  are  laid  in  clusters  of  about  100,  arranged 
in  rows,  each  egg  fastened  on  end,  and  are  laid  on  the  bark  of  the 
smaller  branches  or  on  the  trunk.  The  egg  is  brownish-gray, 
rather  darker  than  that  of  the  spring  species,  and  is  shaped  like 


Fig.  42S. — The  fall  canker  worm  {Alsophila  pometaria):  a,  b,  egg;  c,  d, 
side  and  dorsal  views  of  larval  segment — enlarged;  e,  egg  mass;  /,  larva; 
g,  female  pupa — natural  size;  h,  anal  tubercle — enlarged.     (From  Riley.) 

a  flower-pot,  the  outer  end  being  marked  with  a  dark  spot  in  the 
centre  and  a  dark  ring  near  the  margin.  The  eggs  hatch  in  late 
April  and  early  May  in  Connecticut.  The  larvae  are  very  similar 
in  general  appearance  to  those  of  the  spring  canker  worm,  but 
may  be  easily  distinguished  by  having  two  pairs  of  prolegs  on 
the  middle  of  the  abdomen.     The  pupa  is  similar  to  that  of  the 


574         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


other  species,  but  is  somewliat  stouter  and  the  spine  at  the  tip 
of  the  abdomen  of  the  male  pupa  is  always  forked.  The  cocoon 
is  much  tougher,  contains  more  silk,  and  is  therefore  less  easily 
crushed.  The  male  moth  is  slightly  larger  than  that  of  the  other 
species,  with  longer  antennje,  and  the  wings  are  firmer,  less  trans- 
parent and  darker  in  color.     The  fore-wings  are  crossed  by  two 

whitish  l^ands,  the  _  outer  one  being 
indented  on  the  front  margin  so  that 
it  forms  a  distinct  spot,  and  this  outer 
Ijand  is  seen  on  the  hind- wings,  though 
it  is  less  distinct.  The  females  are  a 
uniform,  ash-gray  without  markings, 
and  with  longer  antennae  than  those 
of  the  other  species,  the  segm.ents  of 
which  arc  about  as  broad  as  long, 
and  are  bare  of  hairs. 

Control. — In  old  sod  orchards  where 
the    pest   is   always   worst,    thorough 
cultivation    will    largely    destroy    the 
1^^^^  ^^^K  pupa)   during   the  summer.     The   cat- 

^S^^^^^^^m  erpllars  may  be  c^uickly  destroyed  by 

^^^^kW^B^  spraying    with    arsenate    of    lead,    3 

^Blr     ^  ^Kfr  pounds,     or     Palis     green,    one-third 

pound,  per  Ixirrel.  The  first  spraying 
should  be  applied  as  soon  as  the  foliage 
is  fairly  expanded  and  before  the 
trees  bloom,  and  the  second  should 
be  given  as  soon  as  the  blossoms 
drop.  Tile  first  is  the  more  im- 
portant and  one  thorough  spraying 
will  usually  suffice,  as  the  young  caterpillars  are  much  more  easily 
killed.  Where  for  any  reason  spraying  is  not  feasible,  the  females 
may  be  prevented  from  ascending  the  trees  by  encircling  the 
trunks  with  bands  of  tanglefoot  or  some  other  sticky  substance 
which  they  cannot  cross.  These  bands  should  be  applied  in  early 
October  and  late  March,  according  to  the  species  prevalent.    The 


Fig.  429.  —  Wingless  fe- 
male moth  and  egg 
mass,  and  winged  male 
moth  of  the  fall  canker 
worm  —  twice  natural 
size.  (After  W.  E. 
Britton.) 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        575 

tanglefoot  may  be  applied  directly  to  the  bark  of  the  tree,  making 
a  band  two  inches  wide  by  one-quarter  inch  thick.  Printer's 
ink,  bodlimc,  and  caterpillar-lime  (raupen-lime)  are  often  used, 
but  should  not  be  placed  on  the  bark.  A  narrow  band  of  cotton 
batting   should    be    run    around    the   tree   and   covered   with    a 


Fig.  430. — Canker  worm  moths  and  egg  masses  caught  on  sticky  band.     (After 

W.  E.  Britton.) 


strip  of  building  paper  4  to  6  inches  wide,  on  the  centre 
of  which  the  sticky  band  should  be  placed,  thus  preventing 
any  injury  to  the  bark  by  the  material.  Where  spraying 
and  cultivation  are  customary  canker  worms  rarely  become 
troublesome. 


576  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Plum  Curculio  * 

Tlirougliout  the  States  east  of  the  Hocky  Mountains,  the  Pkim 
Curcuho  is  one  of  the  worst  pests  of  the  common  stone  and  pome 
fruits.  Its  larva  is  the  common  white  "  worm  "  found  in  peaches, 
phmis,  and  cherries,  w^hile  apples  and  pears  are  scarred  and  gnarled 
by  the  feeding  and  egg  punctures  made  by  the  adults.  It  is  a 
native  insect  which  l)reeds  on  wild  plums,  wild  crab-apples  and 
hawthorns.  The  adult  is  a  thick-set  snout-beetle  about  one- 
quarter  inch  long,  brownish  in  color,  marked  with  gray  and 
black,  and  with  four  black  ridged  tubercles  on  the  wing-covers. 


Fig.  431. — The  plum  curculio  (Conotrachelus  nenuphar  Herbst.):   a,  larva;  b, 
beetle;  c,  pupa — all  much  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

The  larva  is  a  footless,  cylindrical,  whitish  grub,  about  one-third 
inch  long,  with  a  small  brown  head,  and  usually  lies  in  a  curved 
position  as  in  Fig.  431. 

Life  History. — The  beetles  hibernate  under  grass,  leaves,  and 
other  trash  on  the  ground  in  or  near  the  orchard,  or  in  neighboring 
woodlaiids,  and  commence  to  emerge  just  liefore  the  fruit  trees 
bloom  in  the  spring.     They  feed  somewhat  on  the  buds,  unfolding 


*  Conotrachelus  nenuphar  Herbst.  Family  CurculionidoR.  See  C.  S. 
Crandall,  Bulletin  98,  111.  Agr.  Exp.  Sta.;  S.  A.  Forbes,  Bulletin,  108,  ibid.; 
J.  M.  Stedman  Bulletin  64,  Mo.  Agr.  Exp.  Sta.;  E.  P.  Taylor,  Bulletin  21, 
Mo.  State  Fruit  Exp.  Sta.;  A.  L.  Quaintance,  Yearbook  U.  S.  Dept.  Agr., 
1905,  p.  325;  Circular  120,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        577 

leaves  and  blossoms,  but  mostly  on  tli(>  young  fruit  as  soon  as  it 
is  set;    indeed,  in  New  England  the  beetles  do  not  emerge  until 


Fig.  432. — 1,  young  plums  showing  crescent-shapod  egg  punctures  of  the 
pkun  curculio;  2,  adult  curcuho  on  young  peach — four  times  natural 
size.     (After  Quaintance,  U.  S.  Dept.  Agr.) 

a  week  or  two  after  the  apple  blossoms  fall.     The  females  com- 
mence to  lay  eggs  in  the  young  fruits  as  soon  as  formed.     The 


Fig.  433. — Plum  curcuha  on  young 
apple  and  egg  punctures  —  en 
larged. 


Fig.  434. — The  plum  cur- 
culio —  enlarged  five 
times.    (After  Stedman.) 


egg  puncture  of  the  plum   curculio  is  shaped  like  a  crescent  and 
has  given  it  the  very  apt  name  of  "  little  Turk."     The  female 


578      INSECT  PESTS  OF   FARM,  GARDEN  AND  ORCHARD 

first  eats  out  a  small  hole  with  her  stout  snout,  and  deposits  a 
small,  oval,  white  egg  in  the  cavity.  She  then  cuts  a  small  seg- 
ment of  the  skin  and  flesh  around  it  so  that  the  growth  of  the 
fruit  will  not  crush  the  egg,  the  whole  operation  taking  from 
fifteen  to  thirty  minutes.  The  life  of  the  female  averages  about 
two  months,  during  which  time  she  will  lay  100  to  300  eggs  and 
probably  makes  as  many  more  feeding  punctures.  The  punctures 
made  by  the  adults  of  both  sexes  in  feeding  are  simple  round 
holes  like  those  in  which  the  eggs  are  laid,  but  without  the  crescent 


Fig.  435. — Larvae  of  the  plum  curculio — enlarged  five  times.     (After  Stedman.) 

marks.     Frequently  gum  exudes  from   punctures  on  the  stone 
fruits. 

The  egg  hatches  in  from  three  to  five  days  and  the  young 
larva  bores  into  the  fruit  until  grown,  usually  feeding  around  the 
pit  in  stone  fruits.  The  larva  becomes  grown  in  from  twelve  to 
eighteen  days  (in  peaches)  according  to  Quaintancc,  but  in  central 
Illinois  in  fallen  apples  it  requires  from  twenty  to  twenty-six 
days  according  to  Ci'andall.  When  full  grown  the  larva  leaves 
the  fruit  and  enters  the  soil,  where  it  forms  a  small  cell  an  inch 
or  two  below  the  surface,  in  which  it  transforms  to  a  white  pupa. 
Three  or  four  weeks  elapse  before  the  emergence  of  the  adult 


SOME  INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        579 


beetles;  the  first  emerge  about  ten  weeks  after  the  apples 
blossom,  the  majority  appear  two  or  three  weeks  later,  and  the 
rest  continue  to  emerge  until  October.  If  the  weather  is  chy 
the  beetles  may  remain  in  the  cells  much  longer  than  normally, 
while  a  shower  will  bring  out  numbers  of  them.  T'pon  emerging 
the  beetles  feed  upon  the 
ripening  fruit.  In  many 
sections  the  injury  to  ap- 
ples by  the  feeding  punc- 
tures then  made  is  worse 
than  the  spring  injury,  as 
the  surface  of  the  fruit  is 
injured  and  entrance  places 
for  rot  are  furnished.  The 
beetles  average  about  one 
puncture  a  clay  for  six  weeks 
after  emergence  in  central 
Illinois  and  commence  to 
enter  hibernation  with  the 
first  frosts.  In  New  Hamp- 
shire we  have  seen  no  evi- 
dence of  injury  by  the 
beetles  in   late   summer  or         o^^ 


fall. 

Injury.  —  Injured  plums 
and  peaches  usually  drop 
to  the  ground,  or  if  the}' 
remain  on  the  tree,  ripen 
prematurely,  and  rot  more 
quickly.  Clierries  stick  to 
the  tree,  Init  the  fruit  is 
often  small  and  gnarled 
from  the  egg-scars,  or  eaten 
out  by  the  larva.  In  ap- 
ples the  larvse  only  develop  in  those  which  drop  to  the  ground, 
the  rapid  growth  of  the  apples  prol^alily  crushing  the  eggs.     The 


Fig.  433.  — Work  of  the  plum  curculio 
on  apple:  d,  feeding  punctures  from 
surface  and  in  section;  e,  egg  puncture 
from  surface;  e',  same  in  section — 
all  enlarged.     (After  C.  S.  Crandall.) 


580        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

egg-scars  and  feeding-punctures  cause  apples  to  become  gnarly, 
this  Iseing  particularly  true  of  summer  varieties,  which  are  often 
i-endered  worthl(\ss,  and  even  winter  sorts  are  blemished  by  the 
scars  which  also  furnish  points  of  attack  for  rots. 

Control. — Frequent  cultivation  while  the  pupic  arc  in  the  soil 
in  midsummer  will  throw  them  to  the  surface  and  crush  many  of 
them,  and  has  been  found  to  aid  materially  in  the  control  of  the 
pest.     As  the  larvae  often   develop  in   the  fallen  fruit,  it  is  well 


Fig.  437. — Jurrm^  trees  over  a  curculio  catcher,     (.Alter  biuigerland.) 

to  gather  it  every  few  days  and  destroy  it  before  the  larvtc  have 
left  it  to  pupate,  which  will  also  aid  in  the  control  of  other  fruit 
pests.  The  beetles  have  a  habit  of  "  sulling,"  "  playing  possum," 
or  feigning  death,  when  suddenly  disturl^ed,  and  will  droj)  to  the 
ground  if  a  limli  is  jarred.  This  has  given  rise  to  the  common 
practice  of  jarring  peach,  plum,  and  cherry  trees  and  col  ecting 
the  beetles  on  fi-ames  beneath  them.  This  may  be  done  with 
simple  frames  covered  with  canvas,  a  frame  being  placed  on  either 
side  the  tree  and  a  flap  extending  from  one  over  the  edge  of  the 
other,  from  which  the  beetles  are  picked  up,  or  a  regular  curculio- 


SOME   INSECTS  INJURIOUS  TO  ORCHARD  FRUITS        581 

catcher  .such  as  has  been  commonly  used  in  New  York  may  be 
more  convenient.  This  is  used  as  shown  in  P'ig.  437,  the  frame 
being  covered  witli  oil-cloth  and  slanting  to  a  can  containing  kero- 
sene for  the- destruction  of  the  beetles  which  slide  into  it.  The 
jarring  .should  be  done  in  the  morning,  as  the  beetles  do  not  drop 
as  i'(>adily  in  midday.  During  the  past  two  years  extensive 
experiments  have  been  made  in  spra\'ing  with  arsenate  of  lead 
to  poison  the  beetles  while  feeding,  which  show  that  this  is  much 
the  most  satisfactory  method  of  controlling  the  pest.  By  spraying 
with  2  to  3  pounds  of  ar.senate  of  lead  per  barrel  ju.st  after  the 
blossoms  fall,  and  again  three  weeks  later  on- peaches,  and  with 
two  more  sprayings  at  intervals  of  ten  days  on  apples,  from  60 
to  90 per  cent  of  the  injury  from  the  curculio  has  been  jjrevented. 
Only  neutral,  or  nearly  neutral  arsenate  of  lead  should  be  used 
on  stone  fruits,  as  a  slight  amount  of  soluble  arsenious  acid  will 
l)urn  the  foliage  badly.  Paris  green  may  be  used  with  Bordeaux 
mixture  on  apples,  but  does  not  seem  to  be  as  effective  as  arsenate 
of  lead;  and  is  not  advised  for  stone  fruits. 


CHAPTER  XXVII 

INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 
The  Woolly  Apple-aphis  * 

The  Woolly  Aphis  is  one   of  the   most   destructive  pests  of. 
young  apple  orchards,  and  as  it  works  mostly  upon  the  roots  it 
often  escapes  detection  until  the  tree  is  badly  injured  or  killed. 


Fig.  438. — The  woolly  apple-aphis  {Schizoneura  lanigera  Hausm.):  a,  agamic 
female;  b,  young  nymph;  c,  last  stage  of  nymph  of  winged  aphis;  d, 
winged  agamic  female  with  enlarged  antenna  above. — all  gi-eatly  enlarged 
and  waxy  excretion  removed.     (After  Marlatt,  U.  S.  Dept.  Agr.) 

The   aphides  will   be   found   clustered   in    bluish-white,    cottony 
masses,  looking  like  patches  of  mold,  on  the  smaller  twigs,  par- 

*  Schizoneiirn  lanigera  Hausmann.  Family  Aphididce.  See  C.  L.  Mar- 
latt, Circular  20,  Div.  Ent.,  U.  S.  Dept.  Agr.;  R.  I.  Smith,  Bulletin  23,  Ga. 
State  Board  of  Ent.;  Gillette  and  Taylor,  Bulletin  134,  C^olo.  Agr.  Exp.  Sta., 
p.  4;  C.  P.  Gillette,  Journal  of  Economic  Entomology,  Vol.  I,  p.  306. 

582 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


583 


ticiilarly  water-sprouts,  and  around  wounds  or  scars  on  the  trunk 
or  limbs.  Their  presence  in  these  places  is  always  an  indication 
that  others  are  feeding  upon  the  roots,  where  they  cause  gall-like 
swellings,  so  that  the  roots  soon  become  a  mass  of  knots  and  die 
in  a  year  or  two  if  the  injury  continues.  When  badly  attacked 
a  tree  becomes  sickly,  the  foliage  turns  yellow,  and  if  not  killed 
outright  by  the  aphides,  it  falls  an  easy  prey  to  borers  and  other 
pests.  Injury  seems  to  be  worse  on  light  soils  and  not  so  severe 
on  heavy  soils.  Whether  the  insect  is  a  native  or  European 
species  is  a  matter  of  dispute.     In  Europe  it  is  called  the  "  Amer- 


K32 


Fig.  439. — The  wooly  apj^le-aphis :    at  left,  apterous  viviparous  female;    10, 
fall  mio;rant;  11,  over-winter  young.     (After  Gillette  and  Taylor.) 

ican  blight,"  and  was  dcscrilxMl  from  Germany  in  ISOl.  It  has 
now  ])ecome  distributed  all  over  the  world  on  nursery  stock, 
which  forms  the  principal  means  of  its  dissemination. 

Life  History. — On  infested  trees  aphides  will  be  found  in  all 
stages  of  growth  on  the  roots  in  early  spring.  On  the  trunk, 
under  bits  of  bark  or  under  the  dead  bodies  of  those  killed  the 
previous  fall,  will  be  found  numerous  small  aphides  which  have 
hibernated  there,  though  in  the  North  these  may  be  killed  out 
during  severe  winters.  As  the  buds  begin  to  open,  the  aphides 
on  the  trunk  locate  on  tender  new  bark  and  commence  to  feed, 
and  many  migrate  from  the  roots  to  the  top  at  about  the  same 


584         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


time.  They  are  not  usually  detected  until  they  have  multiplied 
sufficiently  to  make  small  white  patches  on  the  bark  or  leaves 
which  look  like  mold.  During  the  spring  and  summer  all  are  w'ing- 
less  females,  not  over  one-tenth  inch  long,  of  a  reddish-brown 
color  and  covered  with  a  white,  waxy  secretion,  given  off  in  threads 
from  the  abdomen  so  as  to  form  a  cottony  mass  over  the  colon}'. 
These  females  produce  from  2  to  20  young  per  day,  which 


^ 

J 

L 

^1 

fe 

^wA^ 

.J 

Fig.  440. — The  woolly  apple-aphis:  at  left,  colonies  on  twig  and  in  scar 
on  an  a]>])le  limb;  at  right,  crown  and  root  of  young  apple  tree,  showing 
characteristic  swellings  produced  by  the  root  ajihides.     (After  Alwood.) 

become  full  grown  in  from  eight  to  twenty  days  according  to 

Alwood,*   100  or  moi-e  probably  being  produced  in  two  weeks. 

Reproduction  continues  on  both  tops  and  roots  except  as  checked 

by  the  cold  of  winter,  the  aphides  l^ecoming  most  abundant  in 

midsummer.     Early  in  the  fall  a  generation  of  winged  aphides 

*  Bulletin  45,  Va.  Crop  Pest  Commission,  p.   12,  Special  Bulletin,  Va. 
Agr.  Exp.  Sta. 


INSECTS   INJURIOUS   TO  THE  APPLE  AND  PEAR  585 


Pig.  441. — Woolly   apple-ai)hides  on   stem   of  seedling  tree  and  swellings 
made  on  roots  slightly  enlarged.     (After  Rumsey  and  Brooks.) 


586        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

appears,  which  migrates  to  other  trees.    They  are  al)out  one-twelfth 
inch  long  and  have  a  wing  expanse  of  one-quarter  inch.     They 


Fig.  442. — Sexual  female  of  the  woolly  apple-aphis,  showing  egg  before  and 
after  extrusion — greatly  enlarged.     (After  Alwood.) 

appear  to  be  black,  but  the  abdomen  is  really  a  dark  yellowish 
or  rusty  brown  color  when  closely  examined,  and  bears  more  or 
less  of  the  waxy  secretion  on  the  tip.      Each  of  these  winged 


Fig.  443. — S(>xual  female  and  male  of  the  woolly  apple-aphis — gi-eatly  enlarged. 

(After  Alwood.) 

females  give  birth  to  from  four  to  six  wingless  males  and  females, 
which  are  deposited  on  the  trunk  of  the  tree.  The  sexes  are 
wingless,  much  smaller  than  the  summer  forms,  and  are  without 


INSECTS  INJURIOUS  TO  THE  APPLE   AND   PEAR  f87 

beaks,  so  that  they  take  no  food.  The  female  is  a  Ijrown-ochre 
color,  antl  the  male  dark  green  or  greenish-brown  and  smaller, 
as  shown  in  Fig.  443.  They  become  full  grown  in  about  eight 
days,  when  they  mate  and  the  female  then  lays  a  single  large  black 
egg,  which  is  deposited  in  the  crevices  of  the  bark  on  the  lower 
part  of  the  trunk.  These  eggs  hatch  in  the  spring  and  give  rise 
to  new  colonics. 

As  they  multiply  large  galls  are  produced  on  the  roots,  the 
tissue  probably  being  poisoned  by  the  mouth-parts  of  the 
insects.  As  a  result  the  roots  soon  die  and  the  aphides  then 
migrate  to  the  growing  roots,  so  that  their  absence  on  the  worst 
knotted  roots  does  not  indicate  that  they  have  forsaken  the 
tree,  but  that  they  are  on  younger  roots. 

Control. — Nurserymen  commonly  apply  a  liberal  amount  of 
tobacco  dust  in  trenches  along  the  rows,  which  kills  the  aphides 
and  acts  as  a  repellant,  as  well  as  being  worth  half  its  cost  as  a 
fertilizer.  This  is  proljably  the  l^est  practice  in  the  nursery  unless 
the  aphides  become  abundant,  when  more  vigorous  treatment 
should  be  used,  but  to])acco  has  not  always  proven  a  satisfactory 
treatment  for  orchard  trees,  though  used  with  apparent  success 
in  some  instances.  The  aphides  may  be  destroyed  on  the  foliage 
by  spraying  with  7  per  cent  kerosene  emulsion,  miscible  oils 
diluted  30  to  40  times,  whale-oil  soap,  1  pound  to  6  gallons,  or 
tobacco  extracts,  "  ))lack  leaf  "  being  used  1  part  in  70  of  water. 
Whatever  insecticide  is  used  must  be  applied  in  a  strong  spray 
so  as  to  thoroughly  wet  and  penetrate  the  waxy  covering  of  the 
aphides.  A  winter  spray  of  lime-sulfur  wash  destroys  the  hiber- 
nating aphides  on  the  trunJc,  and  doubtless  kerosene  emulsion  or 
miscible  oils  applied  in  early  spring,  as  for  the  San  Jose  Scale, 
would  be  as  effective,  though  the  lime  sulfur  would  probably  also 
destroy  some  of  the  eggs.  The  trunks  of  trees  known  to  be 
infested  may  be  Ixmded  with  tanglefoot  or  similar  sticky 
materials  as  described  for  canker  worms  (p.  574)  to  prevent 
the  aphides  from  migrating'  from  the  roots  to  the  top.  Where 
the  aphides  are  abundant  on  the  roots,  the  earth  should  be  removed 
for  6  or  8  inches  deep  over  the  affected  roots  and  10  per  cent 


588        INSECT   PESTS  OF   FARM,    GARDEN   AND  ORCHARD 

kerosene  emulsion  or  dilute  tobacco  extract  should  be  applied, 
using  two  or  three  gallons  per  tree,  or  enough  to  thoroughly 
wet  the  soil.  Dilute  miscible  oil  might  be  used  in  the  same  way. 
Boiling  hot  water  may  be  similarly  applied,  but  is  hardly  prac- 
ticable for  extensive  use.  Carbon  bisulfide  injected  into  the  soil 
has  been  frequenth^  recommended,  l^ut  practical  tests  do  not  seem 
to  demonstrate  its  efficiency.  Badly  infested  nursery  stock  should 
be  destroyed,  and  it  will  be  a  good  practiceto  dip  all  trees  in  hot 
soap  solution,  or  lime-sulfur  wash,  to  destroy  any  aphides  as  well 
as  San  Jose  scale.  It  has  been  observed  that  trees  grown  on 
Northern  Spy  stock  do  not  seem  to  be  as  badly  injured,  and  the 
matter  of  the  susceptibility  of  varieties  should  receive  further  study. 

The  Round-headed  Apple-tree  Borer  * 

The  young  apple  orcliard  must  be  given  frec{uent  inspection 
to  detect  the  work  of  the  round-headed  l^orers,  for  if  they  become 
established  in  the  young  trees  it  is  difficult  to  kill  them  and  they 
soon  girdle  the  trunks.  They  are  most  injurious  to  apple  and 
quince,  less  so  to  pear,  and  also  infest  wild  thornapple  trees  and 
mountain  ash.  The  species  occurs  generally  east  of  the  Kocky 
Mountains,  but  is  not  commonly  injurious  in  the  Gulf  States. 
The  presence  of  the  borers  may  be  detected -by  the  retarded  growth 
of  the  trees,  with  a  yellowing  of  the  foliage,  and  the  sawdust  like 
castings  which  the  larvae  .throw  out  from  the  entrances  of  their 
burrows,  accompanied  by  a  discoloration  of  the  bark  over  the 
new  burrows,  and  in  earl}^  spring  there  is  often  a  slight  exudation 
of  sap.  Injury  is  most  severe  in  neglected  orchards,  where  grass 
and  weeds  are  allowed  to  grow  about  the  bases  of  the  trees,  as 
the  beetle,  which  flies  at  night,  seeks  the  concealment  of  the  rank 
vegetation  during  the  day.  The  parent  beetle  is  a  handsome 
insect  about  three-quarters  inch  long.  The  antennae  and  legs  are 
gray,  the  head  and  under  surface  of  the  body  silvery  white,  and 
the  upper  surface  is  light  brown  with  two  longitudinal  white  stripes. 

*  Saperda  Candida  Fab.  Family  Cerambycidai.  See  F.  H.  Cliittenden, 
Circular  32,  Division  of  Entomology,  U.  S.  Dept.  Agi-.;  E.  P.  Felt,  Bulletin 
74,  N.  Y.  State  Museum,  p.  23,  which  gives  full  bibliography  to  1902. 


INSECTS   INJURIOUS  10  THE   APPLE   AND  PEAR        589 

Life  History. — The  beetles  emerge  from  late  May  to  the  middle 
of  July  and  the  females  soon  commence  to  deposit  their  eggs.  The 
female  eats  out  a  little  slit  in  the  bark,  in  which  the  egg  is  inserted 
and  often  pushed  imder  the  bark  and  then  covered  with  a  gumni}- 
substance.  It  is  a  pale  rust-brown  color,  about  one-third  inch 
long,  of  a  broad  oval  shape,  and  usually  concealed  on  young  trees. 
The  egg  hatches  in  two  or  three  weeks.  The  young  larva?  tunnel 
just  under  the  bark  on  the  sap-wood,  usually  working  down 
toward  the  base  of  the  tree,  the  bark  over  these  burrows  often 


Fig.   444. — The  round-headed    apple-tree  borer    (Saperda  Candida     Fab.) 
larv£e,  adults,  and  exit  hole — natural  size.     (After  Rumsey  and  Brooks). 

cracking  the  next  spring,  and  the  fine  castings  and  Ijorings  sifting 
out.  At  the  beginning  of  the  second  year  the  larva  is  about 
five-eighths  inch  long.  The  larva  continues  in  the  sap-wood 
during  the  second  season,  and  it  is  at  this  time  the  most  serious 
damage  is  done,  for  where  several  occur  in  a  tree  they  almost 
girdle  it.  The  next  season  they  penetrate  into  the  heart-wood, 
and  several  of  them  will  fairly  riddle  a  small  tree  with  their 
cylindrical   borrows.     The  full-grown  larva  continues  this  burrow 


590 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


out  into  the  bark,  often  cutting  clear  across  a  tree.  The  upper 
part  of  the  burrows  are  stuffed  with  fine  borings  and  the  lower 
part  with  long  wood  fibres.  The  full-grown  larva  is  a  light 
yellowish,  cylindrical  grul3,  al^out  three-quarters  inch  long.  The 
head  is  small,  legs  are  lacking,  and  the  liody  tapers  gradually 
from  the  thorax  backward,  the  segments  bcsing  quite  constricted. 
The  third  spring  the  larvae  transform  to  pupic  and  al)Out  three 
weeks  later  the  adult  beetles  emerge  through  large  round  holes. 

Control. — The  females  may  be  prevented  from  laj'ing  their 
eggs  by  wrapping  the  trunks  with  wire  netting,  building  paper, 


Fig.  445. — Work  of  the  round-headed  apple-tree  borer:  a,  puncture  in 
which  egg  is  laid;  b,  same  in  section;  e,  hole  from  which  beetle  has 
emerged;  /,  same  in  section;  g,  pupa  in  its  cell.     (After  Riley. "> 

or  wood  veneer.  If  non-rusting  wire  netting  is  used  it  may  be 
left  on  and  will  also  protect  the  trees  from  mice  and  rabbits. 
The  paper  or  wood  wrappings  should  be  applied  about  May  1st, 
and  removed  in  late  summer.  They  should  be  tied  to  the  tree 
tightly  just  below  the  crotch  and  should  extend  an  inch  or  two 
into  the  soil  below.  The  wire  netting  should  be  held  out  from 
the  trunk  of  the  tree  l^y  a  layer  of  cotton  batting  under  it  at  the 
upper  end.  Various  washes  have  been  used  to  repel  the  beetles. 
Thick  whale-oil  or  caustic  soft-soap  to  which  a  pint  of  crude 
carbolic  acid  is  added  to  every  10  gallons  is  often  used  and  should 


INSECTS  INJURIOUS  TO  THE  APPLE    AND  PEAR 


591 


be  painted  over  the  trunk  so  as  to  form  a  thick  coating.  Others 
recommend  a  thick  coating  of  whitewash  to  which  a  little  Port- 
land cement  is  added  to  make  it  more  adhesive.  These  should 
be  applied  by  the  middle  of  May  and  as  often  as  need  be  to  keep 
the  trunk  covered  until  late  summer.  If  the  trees  are  gone  over 
every  fall  and  sirring,  the  egg  scars  and  burrows  of  the  young 
larviu  may  be  detectetl  and  tlie\'  may  be  cut  out  while  still  in  the 
sap-wood,  without  much  injury  to  the  tree.  When  the  borers 
get  into  the  heart-wood  it  is  almost  impossible  to  dig  them  out  with- 
out doing  more  injury  to  the  tree,  but  they  may  sometimes  be  de- 
stroyed by  injecting  carbon  bisulfide  into  the  burrows  and  plugging 
the  aperture  with  putty  or  clay.  Where  a  tree  has  been  nearly  or 
quite  girdled,  it  may  sometimes  be  saved  by  bridge-grafting. 
Orchards  kept  free  of  grass  and  weeds  and  trees  with  smooth 
healthv  bark  are  much  less  affected. 


The  Flat-headed  Apple- tree  Borer  * 

This  species  is  more  abundant  than  the  preceding,  but  does 
less  damage.  It  prefers  trees  which  have  been  weakened  or  are 
diseased,  and  attacks  almost  all  of  the  common  orchard  trees  as 
well  as  numerous  shade  and  forest  trees,  so  that  it  is  everywhere 
common.  The  species  is 
found  from  southei-n  Can- 
ada to  Mexico.  The  larvae 
live  just  beneath  the  bark, 
where  they  hollow  out 
broad  flat  channels  which 
extend  slightly  into  the 
sap-wood.  The  infestation 
may  be  detected  liy  the 
discoloration  of  the  Ijark. 
Where  abundant  they  will 
often  completely  girdle^ 
young  trees,  thus  causing 
their   death,    and    th(>y   are    frequently    found    alnindant   under 

*  Chrysobuthrls  femorata  Fab      Family  Buprestidae.     See  Chittenden,    I.e. 


Fig.  446.— The  flat-headed  apple-tree 
borer  iChrysobothris  femorata  Fab.): 
a,  larva;  b,  beetle;  c  head  of  male; 
(I,  pupa — twice  natural  .size;  (After 
Chittenden,  U.  S.  Dept.  Agr.) 


592  INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  loosening  bark  of  the  dying  Hmbs  of  large  trees,  as  they 
infest  not  only  the  trunks,  but  the  lower  limbs.  The  adult  beetle 
is  about  one-half  inch  long,  dull  metallic  brown  above,  and  the 
wang-covers  taper  sharply  at  the  tip,  somewhat  like  a  click  beetle. 
The  wing-covers  are  ornamented  as  shown  in  the  figure,  and 
beneath  them,  as  seen  when  in  flight,  the  body  is  a  bright  metaUic 
greenish-blue.  The  male  is  smaller  and  the  head  is  green.  The 
beetles  are  active  during  the  heat  of  the  day  and  may  often  be 
found  on  logs  or  injured  trees. 

lAfe  History. — The  beetles  emerge  from  the  middle  of  ilay  until 
mid-summer.  The  eggs  are  deposited  in  crevices  of  the  bark, 
several  often  being  laid  together.  The  eggs  are  yellowish, 
irregularly  ribbed  and  about  one-fiftieth  inch  long.  The  species 
receives  its  name  from  the  shajje  of  the  larva,  the  thorax  of  which 
is  very  broadly  expanded,  so  that  it  looks  like  the  head,  which  is 
very  small  and  almost  concealed  by  it.  The  alxlomcu  is  much 
smaller  and  the  Avholo  body  is  flattened.  The  larva  is  about 
one  inch  long^  and  usually  rests  in  tlie  curvi^d  position  shown  in 
Fig.  446.  The  larva  becomes  full  grown  in  a  single  }-ear  and  in  the 
South  may  pupate  in  November,  but  in  the  North  does  not  pupate 
until  the  next  spring,  when  it  remains  as  a  pupa  about  three  weeks. 
The  beetle  emei-ges  through  an  elliptical  exit  hole,  in  contrast  to 
the  round  hole  of  the  round-headed  borer. 

Control. — As  this  beetle  is  everywhere  present,  injury  may 
always  be  expected  if  trees  are  not  kept  in  a  healthy  condition, 
but  if  the  orchard  is  well  cared  for  it  seldom  does  much  damage. 
The  same  measures  for  preventing  oviposition  as  suggested  for 
the  previous  species  are  advised,  Ijut  the  repellant  washes  must  be 
applied  higher  on  the  trunks  and  should  extend  to  the  lower 
branches  as  high  as  can  be  reached. 

The  Oyster-shell  Scale  * 

Not  infrequently  young  apple  and  pear  trees  are  encrusted  and 

killed  by  the  Oyster-shell  Scale,  as  are  young  poplars  and  maples. 

*  Lepidosaphes  ulmi  Linn .  Family  Cuccldce.  See  Quaintance  and 
Sasscer,  Circular  121,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  and  refer- 
ences there  given. 


INSECTS   INJURIOUS  TO    THE  APPLE   AND  PEAR 


593 


It  is  probably  our  most  common  scale  insect,  being  almost  always 
found  on  apple  trees,  on  which  it  works  on  the  bark  or  the  twigs 
and  trunk,  reproducing  even  on  old  trunks,  where  the  scales  will 
be  found  under  the  loose  bark  and  are  luidoubtedly  a  factor  in 
causing  the  bark  to  slough  off.  All  of  the  common  orchard  trees 
are  occasionally  infested  but  rarely  injured,  as  are  also  maple, 
poplar,  horse-chestnut,  willow  and  lilac.     Quaintance  and  Sasscer 


FiG.  447. — The  oyster-shell  scale  {Lepidosaphcs  idmi  Linn.):  a,  female 
scales  on  twig;  b,  female  scales  from  above;  c,  same  from  below  showing 
eggs;  d,  male  scale — enlarged.     (After  Howard.) 


give  a  list  of  over  100  trees,  shrubs,  and  plants  upon  which  the 
scales  have  been  found.  The  species  is  a  cosmopolitan  one, 
being  introduced  into  this  country  at  an  early  date  and  now 
being  found  in  every  State,  and  occufs  throughout  the  world  where 
the  food-plants  exist. 

The  mature  female  scale  is  about  one-eighth  inch  long,  of  a 
dark-brown  color,  sometimes  almost  blackish,  and  shaped  some 
what  like  an  oyster-shell,  as  shown  in  Fig.  447.     The  male  scale  is 


594       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


much  smaller,  and  with  but  one  cant  .skui  at  the  anterior  end,  as 
shown  in  the  same  figure. 

Life  History. — If  one  of  the  female  scales  be  turned  over  during 
the  winter,  numerous  oval,  white  eggs  will  be  found  under  it, 
with  the  shriveled  body  of  the  female  insect  tucked  away  at  the 
anterior  end.  These  eggs  hatch  a  week  or  two  after  the  apples 
blossom,  producing  small  yellowish  insects,  which  look  like  mites 
as  they  crawl  over  the  bark,  which  they  often  give  a  yellowish 


Fig.  448. — The  oyster-shell  scale:  a,  adult  male;  6,  foot  of  same;  c,  young 
nymph;  d,  antenna  of  same;  e,  adult  female  taken  from  scale — a,  c, 
e,  greatly  enlarged,  b,  d,  still  more  enlarged.  (After  Howard,  U.  S. 
Dept.  Agr.) 

tinge  where  very  abundant.  The  young  insect  is  of  microscopic 
size  and  is  shown  greatly  enlarged  in  Fig.  44S,  c.  It  settles  down 
after  a  few  hours'  wandering  and  begins  sucking  the  sap  from 
the  bark.  In  a  day  or  two  long,  white  waxy  filaments  exude 
from  over  the  body,  which  soon  mat  down  and  form  the 
protecting  scale,  to  which   the   cast  skins  are  added  when  the 


INSECTS    INJURIOUS    TO    THE    APPLE  AND   PEAR         595 

insect' molts.  The  foinulc  loses  her  legs,  antennic,  and  eyes,  after 
the  first  molt,  and  when  full  grown  is  an  elongate,  yellow- 
ish, jelly-like  mass,  l)eing  simply  a  "  reproductive  sack,  with  her 
sucking  mouth  parts,  through  which  the  food  is  taken,  inserted  in 
the  tissues  of  the  plant,"  as  shown  in  Fig.  448,  e.  The  females 
become  full  grown  in  about  eight  to  ten  weeks,  when  they  lay 
from  40  to  100  eggs  and  then  die.  In  the  North  there  is  but  one 
generation  a  }'ear,  but  from  the  District  of  Columbia  southward 
there  is  a  partial  or  complete  second  generation.  When  the  male 
insects  are  full  grown  they  emerge  from  the  scales  as  two-winged 
flies,  as  shown  greatly  enlarged  in  Fig.  448,  at  a,  fertilize  the 
females  and  die  at  once. 
Control. — See  below. 

The  Scurfy  Scale  * 

"  The  Scurfy  Scale,  while  infesting  a  considerable  number  of 
plants  (some  35  in  number),  is  a  less  general  feeder  than  the 
preceding  species.  It  occurs  principally  upon  rosaceous  plants, 
such  as  the  apple,  peach,  pe.ir,  plum,  cherry,  etc.,  and  also  on 
currant  and  gooseberry  among  cultivated  plants,  but  seldom 
becomes  so  abundant  as  to  cause  particular  injury  or  require 
specific  treatment."  It  is  especially  common  on  apple  and  pear 
and  less  so  on  cherry  and  peach,  though  it  has  been  observed  as 
quite  destructive  to  peach  in  the  South,  greatly  stunting  the 
trees,  though  none  were  actually  killed.  The  female  scale  is  a 
dirty-gray  color,  irregularly  shaped  as  shown  in  Fig.  449,  c. 
The  male  scale  is  much  smaller,  elongate,  snowy  white,  and  with 
three  distinct  ridges.  Fig.  449,  (I.  It  is  an  American  insect,  being 
common  from  southern  Canada  to  the  Gulf  States.  The  life 
history,  as  far  as  known,  is  practically  identical  with  that  of  the 
last  species. 

Control. — As  the  last  two  species  are  practically  identical  in 
habits,  they  may  be  controlled  by  the  same  methods.  Where 
the  trees  are  spraj^ed  with  lime-sulfur  wash  for  the  San  Jose 

*  Chiomispis  fiirfiira  Fitch.  Family  Coccidce.  See  Quaiutance  and 
Sasscer,  I.e. 


596       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

scale,  there  will  be  but  little  trouble  with  these  scales,  and  where 
specific  treatment  is  required  for  them  experiments  indicate 
that  a  thorough  coating  with  the  lime-sulfur  wash  while  the  trees 
are  dormant,  preferably  in  the  spring  just  before  the  buds  open, 
is  one  of  the  most  effective  remedies.  The  wash  does  not  seem 
to  kill  the  eggs,  but  to  kill  the  young  soon  after  hatching,  and  has 
been  used  successfully  on  both  fruit  and  shade  trees,  but  if  there 
be  frequent  rains  in  late  spring,  so  that  it  is  washed  off,  or  if  the 


Fig.  449. — The  scurfy  scale  {Chionaspis  furfura  Fitch):  a,  c,  females, 
b,  d,  males — a,  h,  natural  size,  c,  d,  enlarged.  (After  Howard,  U.  S. 
Dept.  Agr.) 

scales  are  very  thick,  it  is  not  always  entirely  effective.  In 
England  a  3  per  cent  caustic  soda  wash  has  proven  very  satisfactory 
for  killing  the  winter  eggs.  Recent  experiments  made  by  Professor 
R.  A.  Cooley  in  Montana  *  show  that  emulsions  of  linseed  or 
cottonseed  oils  are  very  satisfactory  when  applied  either  in  the 
spring  or  as  the  eggs  are  hatching,  and  were  more  effective  than 

*  R.  A.  Cooley,  Journal   of  Economic  Entomology,  III,^p.   57;  R.  L. 
Webster,  ibid.  IV,  p.  202. 


INSECTS  INJITRIOUS  TO  THE  APPLE  AND  PEAR  597 

other  insecticides  tested.  These  emulsions  are  prepared  the  same 
as  kerosene  emulsion  (p.  4S),  using  one  gallon  of  the  oil,  and 
h  to  1  pound  of  soap  to  10  or  12  gallons  of  water.  When  the  eggs 
arc  hatching  and  the  young  arc  crawling  the  trees  maybe  sprayed 
with  the  al)ovc  or  lo  per  cent  kerosene  emulsion,  or  whale-oil 
soap.  1  pound  to  4  or  o  gallons  of  water.  The  effectiveness  of 
the  last  two  insecticides  seems  to  vaty  according  to  local  conditions, 
as  they  have  proven  satisfactor}'  in  certain  experiments  and  of 
less  value  in  others.  As  for  the  San  Jose  scale,  the  trees  or  shrubs 
to  be  treated  should  first  be  pruned  of  the  dead  and  worst-infested 
wood,  and  loose  bark  scraped  off,  so  that  the  bark  may  be  thor- 
oughly covered. 

Apple  Plant-lice  * 

Several  species  of  aphides  or  plant -lice  commonh'  infest  the 
foliage  of  the  apple,  and  less  commonly  that  of  the  pear,  and 
though  they  differ  somewhat  in  appearance  and  habits  they  are 
sufficiently  alike  to  bo  discussed  together,  as  the  same  methods 
of  control  apply  to  all. 

The  Apple-aphis  f 

This  is  the  common  apple-aphis  of  Europe,  and  was  first 
noticed  in  this  country  late  in  the  last  century,  when  it  spread  to 
all  parts  of  the  country  wdthin  a  few  years,  probably  being  dis- 
tributed on  nursery  trees.  Only  young  trees  are  usually  much 
injured  by  this  and  the  following  species  of  aphides,  old  trees 
rarely  being  injured,  ex*cept  that  where  the  aphides  are  excess- 
ively abundant  they  sometimes  injure  the  young  fruit,  causing 
it  to  become  stunted  and  misshapen.  The  foliage  of  young  trees 
soon  becomes  covered  with  the  vermin,  which  feed  on  the  under 
surfaces  of  the  leaves,  causing  them  to  ciui  up  and  then  drop. 

*See  Sanderson,  13th  Report,  Del.  Agr.  Exp.  Sta.;  A.  L.  Quaintance, 
Circular  81,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Gillette  and  Taylor, 
Bulletin  133,  Colo.  Agr.  Exp.  Sta. 

t  ApJiis  pomi  DeG.  Family  ApJiididoe.  See  above  references,  and  J.  B. 
Smith,  Bulletin  143,  N.  J.  Agr.  Exp.  Sta.;  C.  P.  Gillette,  Journal  of  Economic 
Entomology,  Vol.  I,  p.  303. 


598        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

This  curling  of  the  foliage  is  more  commonly  caused  by  this 
species  than  any  other,  though  the  rosy  apple-aphis  has  a  similar 
effect.  The  aphides  secrete  the  sweet  honey-dew  very  profusely 
and  so  attract  large  numl^ers  of  ants,  which  feed  upon  it.  The 
ants  are  always  found  associated  with  them,  and  the  presence  of 
numerous  ants  on  a  tree  is  a  good  indication  of  aphides.  The 
honey-dew  soon  covers  l^adly  infested  foliage  and  upon  it  there 


ij>ii^:^l-:. 


Fig.  450. — The  apple-aphis  (Aphis  pomi  DeG.):  1,  young  stem  mother; 
2,  adult  stem  mother;  3,  adult  apterous  viviparous  female;  second 
generation;  4,  young  female,  second  generation;  5,  winged  viviparous 
female  of  third  generation;  6,  pupa  of  preceding;  7  and  8,  apterous 
male  and  oviparous  female — all  enlarged  as  indicated.  (After  Gillette 
and  Taylor.) 

grows  a  blackish  fungus  which  gives  the  leaves  a  sooty  appear- 
ance, often  visible  on  the  twigs  after  they  drop,  and  a  good 
indication  of  injury  b}'  this  species.  The  full-grown  wangless 
females  are  about  one-twelfth  inch  long,  and  shaped  as  shown 
in  Fig.  450.     They  are  of  a  bright  green  color,  though  occasion- 


INSECrrS   TNJUIMOITS  TO  THE   Al'l'Li:    AND    I'lvMl 


590 


ally  yellowish,  and  the  tips  of  the  anteniite,  honey-tubes,  and  tail 
are  black.     The  winged  female  is  slightly  longer  and  the  wings 


Fig.  451. — The  apple-aphis,  winged  viviparous  female— greatly  enlarged. 

expand    about  one-quarter  inch,  the  head  is  deep  olive  brown; 
the  thorax  is  blackish,  and  there  are  three    black  spots  on  the 


Fig.  452. — Xymphs  of  the  ai)ple-aphis,  clustered  on  a  leaf,  showing  developing 

wing-pads. 

lateral  margin  of  the  alxlomen,  l)ut  otherwise  it  is  colored  like  the 
wingless  female. 

Life    History. — The    minute,    oval,    shining    black    eggs    are 


600 


INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


to  be  found  on  the  twigs  during  the  winter,  especially  at  the 
crotches  and  around  buds  and  scars.  They  hatch  just  before 
the  leaf  buds  open  and  the  young  aphides  become  full  grown  in 
two  or  three  weeks,  all  of  them  being  wingless.  During  the  next 
two  or  three  weeks  each  of  these  females  will  give  birth  to  from 
50  to  100  3'oung,  a  few  of  which  develop  wings.     All  of  the  aphides 


Fig.  453. — The  apple-aphis;    a,  young  tree  partially  defoliated  by  the  aphis; 
d,  winter  eggs  on  twig. 

of  this  second  generation  are  also  females,  which  give  birth  to 
live  young  without  the  intervention  of  males,  which  do  not  appear 
until  fall.  Their  3'oung  develop  in  a  week  or  ten  days  and  most 
of  them  become  winged  and  migrate  to  other  trees.  The  develop- 
ment and  reproduction  continues  in  this  fashion  throughout  the 
summer.  Ijoth  winged  and  wingless  females  being  found  in  most 
colonies,   though  the   size  and    coloration    differ  in  the   various 


INSECTS    INJURIOUS  TO   THE  APPLE   AND  PEAR  601 

generation.s.  Those  whicli  arc  to  become  winged  may  be  dis- 
tinguished after  the  third  molt  by  the  bhickish  wing-pads  at 
the  sides  of  the  body,  ^^'ith  the  first  frosts  of  fall  the  young 
develop  into  true  males  and  females.  Both  are  wingless,  the 
male  being  much  the  smaller,  has  long  antennae,  is  yellowish  or 
rusty-brown,  and  is  very  active,  while  the  female  is  larger,  moves 
more  slowly  and  is  lighter  in  color,  but  later  becomes  a  very 
dark  green.  The  sexes  mate  and  the  females  lay  1  to  3  eggs  in  the 
places  mentioned.  All  of  the  aphides  die  by  late  fall  and  the 
eggs  remain  to  give  rise  to  new  colonies  in  the  spring. 

"With  the  rapid  multiplication  above  described  it  is  not  surpris- 


FiG.  454. — The  apple-aphis,  winged  fall  migrants  on  leaf — natural  size. 

ing  that  tlie  foliage  is  soon  covered  with  thousands  of  aphides, 
and  that  with  so  numy  sucking  the  sap  the  leaves  soon  curl  up 
and  drop.  This  is  often  a  serious  drain  upon  the  vitality  of 
young  trees,  stunting  their  growth,  and  so  weakening  them  that 
they  are  more  liable  to  be  attacked  by  other  insects  and  diseases, 
while  the  premature  dropping  of  the  foliage  prevents  the  full 
growth  of  the  tree  and  the  proper  hardening  of  the  wood  before 
winter.  This  species  shows  marked  preference  for  certain  varieties 
of  apples  and  rarely  injures  others.  Apple,  pear  and  quince  are 
the  onl}'  fruit  trees  infested  by  this  species,  which  lives  upon 
them  throughout  the  year. 


602        INSECT   PESTS   OF   FARM,  GARDEN  AND   ORCHARD 

The  Rosy  Apple-aphis  * 

This  species  is  larger  than  the  preceding,  with  a  rounder  body, 
and  is  commonly  of  a  rosy  color,  though  the  wingless  females 
vary  from  a  salmon  or  tan  color  to  slaty  gray,  purplish  or  black. 
It  has  been  injurious  only  to  apple  in  this  country,  where  it  has 
become  widely  distributed,  but  in  Europe  its  native  food-plants 
are  various  wild  species  of  Sorbus  and  Cratcegus.  The  wingless 
female  is  about  one-tenth  inch  long,  the  head,  thorax  and  margin 
of  the  abdomen  being  dark  reddish-ljrown,  and   covered  with  a 


Fig.   455. — The  rosy   apple-aphis    {Aphis  sorbi   Kalt.):   winged   vivii)arous 
female  greatly  enlarged, 

powdery  substance  which  gives  it  a  deep  blue  color,  the  middle 
of  the  abdomen  being  lighter  yellowish.  The  antennae  and  legs 
are  whitish,  marked  with  dusky.  The  honey-tubes  are  pale  yellow, 
tipped  with  black,  and  are  long  and  tapering.  Between  the  eyes 
are  two  sma'l  tubercles,  and  on  the  middle  of  the  two  segments 
in  front  of  the  tail  are  a  pair  of  similar  small  tubercles,  which 
are  quite  characteristic  of  this  species.  When  fully  developed 
the  female  becomes  much  darker  and  distended  with  young,  which 

*A2^/iissor6iKaltenbach.  Family  Aphididoe.  See  Sanderson,  and  Gillette 
and  Taylor  {Aphis  pyri  Boyer),  cited  above;  and  W.  E.  Britton,  9th  Report, 
State  Entomologist  of  Connecticut,  p.  343. 


INSECTS  INJURIOUS   TO   THE  APPLE  AND  PEAR  003 

may  be  seen  through  the  abdomen.  The  wingetl  female  is  about 
the  same  length,  the  head,  thorax  and  honey-tubes  being  black, 
and  the  abdomen  yellowish-red.  The  winged  females  in  the  fall 
differ  from  those  of  the  spring  in  lacking  the  small  tubercles 
between  the  eyes,  but  both  spring  and  fall  winged  females  have 
the  two  pairs  of  small  tubercles  in  front  of  the  tail.  The}-  also 
differ  in  having  a  large  black  splotch  on  the  centre  of  the  abdomen, 
bands  across  the  terminal  abdominal  segments,  and  spots  along 
the  sides,  also  black.  The  male  is  winged  and  similar  to  the  winged 
viviparous    females   which   migrate   back   to   the   apple  in  fall. 

The  egg-laying  females  are 
wingless,  very  much  smaller 
than  the  summer  forms,  and 
light  lemon-yellow  in  color. 

Life  History. — The  eggs  oc- 
cur on  the  twigs,  as  do  those 
of  the  last  species,  hatch  about 
the  same  time,  and  the  first 
two  or  three  generations  de- 
velop on  the  app  e  in  the 
same  manner.  Like  the  last 
species,  the  third  generation 
is  mostly  winged  females 
Fig.  456.-The  rosy  apple-aphis  wingless  .^j^j  migrate  from  the  apple 
viviparous  lemale — greatly  enlarged.  ^  ^ 

to  some  unknown  footl-plant, 

on  which  the}'  pass  the  summer.  The  wingetl  females  return  to 
the  apple  foliage  in  the  fall  and  then  give  birth  to  young,  which 
develop  into  the  true  males  and  females,  which  may  be  found  laying 
their  eggs  in  company  with  the  last  and  other  species. 

This  species  curls  the  leaves,  as  does  the  apple-aphis,  and  is 
likewise  accompanied  by  ants.  Dr.  Britton  states  that  "  the 
rosy  apple-aphis  .  .  .  seems  especially  prone  to  attack  the  fruit 
spurs  and  inner  portions  of  the  tree-top  rather  than  the  terminal 
twigs  and  exterior  part,"  and  that  it  "  affects  seriously  the 
growth  of  the  fruit,"  preventing  its  growth  and  development, 
and  causing  it  to  be  gnarled  and  irregular  in  shape,  similar  to  the 
damage  sometimes  observed  by  the  last  species. 


604       INSECT  PESTS  OF  FARM,  GARDEN   AND  ORCHARD 

The  European  Grain-aphis  * 

This  species  is  found  on  the  apple,  pear,  quince  and  plum  in  the 
spring  and  fall  and  on  the  small  grains  and  various  grasses  during 
the  summer.  Until  recently  it  has  been  the  more  common  form 
on  apple  in  the  East,  but  is  not  now  so  numerous  as  the  apple- 
aphis.  It  is  an  old  European  species  and  was  evidently  imported 
to  this  country  at  an  early  date,  as  it  is  widely  distributed  through- 
out   the    United.  States.     The    wingless    females    are    distinctly 


Fig.  457. — The  European  grain-aphis  (Siphocoryne  avencB  Fab.):    wingless 
viviparous  female,  and  egg-laying  or  oviparous  female — greatly  enlarged. 

smaller  than  the  previous  species,  and  are  of  a  light  green  color, 
marked  with  transverse  diamond-shaped  bands  of  darker  green 
across  the  abdominal  segments.  The  honey-tubes  are  shorter, 
distinctly  enlarged  at  the  middle  and  flared  at  the  tip,  which 


*  Siphocoryne  avenae.  Fab.  Family  Aphididce.  See  Th.  Pergivnde,  Bulletin 
44,  n.  s.,  Div.  Ent.,  U.  S.  Dept.  Agr.,  p.  5  and  authors  cited  above.  The 
author  descril^ed  this  species  as  Aphis  fitchii  in  1902,  and  although  there 
seems  to  be  no  question  that  it  feeds  on  grains  and  grasses  during  the  summer, 
there  are  several  reasons  for  believing  that  there  are  either  two  species  or 
that  the  life  history  has  not  been  sufficiently  observed.  Thus  in  some  sections 
it  is  exceedingly  common  on  grain  but  rare  on  apple,  and  in  others  just  the 
opposite  condition  is  found.     Further  observation  may  solve  these  anomalies. 


INSECTS   INJURIOUS   TO   THE   APPLE    AND    PEAR 


605 


distinguish  the  species  of  this  genus.  The  winged  female  has 
the  head  and  thorax  blackish,  and  the  abdomen  yellowish-green 
or  brownish,  usually  lacking  the  greenish  Ixmds  of  the  wingless 
form,  and  the  honey-tubes  are  brown  with  rusty  spots  around  the 
base.  The  species  may  be  distinguished  by  the  very  short  second 
fork  of  the  median  vein  at  the  tip  of  the  fore- wings. 

Life  History. — The  eggs  are  found  on  the  apple  and  pear,  and 
the  first  two  generations  in  the  spring  develop  as  do  those  of  the 


Fig.  458. — The  European  grain-aphis,  migrating  winged  viviparous  female 
of  the  second  generation — greatly  enlarged. 

preceding  species.  All  of  the  second,  or  sometimes  the  third, 
generation  become  winged  and  migrate  to  small  grains  and 
grasses,  on  which  they  feed  during  the  summer.  .In  the  fall 
winged  females  return  to  the  fruit  trees  and  give  birth  to  young, 
which  develop  into  wingless  females  and  winged  males,  which  mate 
and  produce  the  winter  eggs.  Pergande  states  that  "  the  species 
is  biennial  and  that  the  progeny  of  the  spring  migrants  from  the 
apple  subsist  almost  exclusively  upon  various  grains  and  grasses 
until  the  fall  of  the  second  year,  when  a  generation  of  return 
migrants  makes  its  appearance."  This  is  certainly  true  in  the 
South,  where  the  aphides  may  be  observed  on  grains  throughout 


606         INSECT   PESTS   OF   FARM,   GARDEN   AND   ORCHARD 

the  winter,  but  it  may  be  questioned  whether  they  usually  survive 
the  winter  on  grains  or  grasses  in  the  North. 

Professor  F.  M.  Webster*  has  observed  this  species  on  wheat  in 
Ohio,  and  states  that  in  mild  winters  it  remains  on  the  wheat, 
going  down  on  the  stems  to  just  below  the  surface  of  the  soil  or 
to  the  upper  roots,  as  we  have  observed  it  in  Texas.  "  Here  they 
go  on  reproducing  when  the  temperature  is  favorable/'  he  says, 
"  the  adults  being  apterous  so  far  as  observed  by  me,  until  spring, 
when  they  ascend  to  the  foliage,  the  adults  after  this  being  both 
winged  and  wingless.  On  the  stems  and  roots  below  the  surface 
of  the  ground  they  arc  of  a  greenish  color,  tinged  with  reddish- 
brown,  especially  posteriorly,  the  full-grown  individuals  often 
being  wholly  of  a  dark  brown.  It  is  during  autumn  that  they 
do  their  greatest  injury  to  the  wheat  by  sucking  the  juices  from 
the  young  plants,  often,  if  on  poor  land  and  if  in  dry  weather, 
checking  their  growth  and  causing  the  foliage  to  turn  yellow." 
This  species  is  seldom  much  in  evidence  on  grains  or  grasses  in 
midsummer  and  rarely  becomes  very  injurious  to  them.  On 
the  apple  it  is  abundant  on  the  young  foliage  and  particularly 
on  the  flower  buds  and  blossoms,  where  it  is  much  more  common 
than  the  other  species.  It  does  not,  however,  curl  the  foliage 
nearly  as  severely  as  the  other  species,  due  to  its  earlier  migra- 
tion. 

The  Clover-aphis  f 

This  species  is  more  particularly  a  clover  pest,  but  is  mentioned 
because  it  oviposits  on  apple  and  pear  and  may  be  confused  with 
other  species  in  spring  and  fall.  It  has  been  observed  in  Colorado 
and  has  been  injurious  to  clover  in  Iowa,  but  its  further  distribution 
is  vmknown.  The  wingless  female  of  the  first  generation  varies 
from  a  dark  green  streaked  and  mottled  with  red  to  a  deep  dark 
red,  with  honey-tubes  very  short  and  pale  yellow  throughout. 
The  second  generation    are   light   green   or  yellowish-green   and 

*  See  Bulletin  51,  Ohio  Agr.  Exp.  Station,  p.  111. 

t  Aphis  bakeri  Cowen.  Family  Aphididce.  See  Gillette  and  Taylor,  I.e.; 
C.  P.  Gillette,  Journal  Economic  Ent.,  Vol.  I,  p.  364. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND   PEAR  607 

the  summer  generations  on  clover  are  pink  or  yellowish,  with 
a  large  pale  orange  spot  around  the  base  of  each  honey-tube. 
Concerning  this  species  Gillette  and  Taylor  give  the  following: 
''  The  clover  aphis,  A.  bukeri,  infests  the  cultivated  and  sweet 
clovers  and  alfalfa  throughout  the  warmer  part  of  the  year  where, 
apparently,  it  never  occurs  in  the  oviparous  form  nor  as  eggs. 
In  the  fall  a  portion  of  the  winged  lice  migrate  to  apple  and  pear 
trees,  where  eggs  are  deposited  to  live  over  winter  and  hatch  into 
the  red  stem  mothers  the  following  spring,"  hatching  a  week  or 
two  before  the  apple-aphis.  "  The  descendants  of  these  stem 
females  begin  in  the  second  generation  to  get  wings  and  by  the 
middle  of  June  nearly  all  have  left  the  trees  and  gone  back  to  the 
clovers,  though  some  remain  on  the  apple  all  summer.  In  the 
fall,  many  of  the  lice  continue  upon  the  clovers,  going  down  close 
to  the  ground  as  cold  weather  comes  on,  and  if  the  winter  is  not 
very  severe,  many  will  survive  and  continue  to  live  and  increase 
upon  these  plants  throughout  the  year.  So  far  as  our  observa- 
tions have  gone  this  louse  ranks  next  to  the  green  apple-aphis 
{Aphis  pomi)  in  numbers  as  a  leaf-infesting  species  of  the  apple, 
.  .  .  but  we  can  hardly  consider  it  a  serious  pest  as  yet  in  Colorado 
orchards."  Evidently  the  life  history  closely  parallels  that  of  the 
previous  species,  S.  avence. 

Control. — Recent  experiments  have  shown  that  lime-sulfur 
wash  applied  while  the  trees  are  dormant,  as  for  the  San  Jose 
scale,  will  kill  nearly  all  aphid  eggs.  Pure  crude  petroleum  has 
also  proven  effective  against  the  eggs  in  several  experiments. 
Recently  Professor  Gillette  has  reported  *  experiments  which 
indicate  that  tobacco  extracts  will  destroy  the  eggs  when  used  at 
various  dilutions  according  to  the  strength  of  the  extract,  l)ut 
though  these  preparations  may  be  effective,  further  field  experi- 
ments will  be  necessary  to  determine  the  exact  dilution  best  for 
orchard  use.  Spraying  for  the  aphides  after  they  hatch  should  be 
done  before  they  commence  to  curl  the  leaves,  preferably  just  as  the 
foliage  is  expanding,  for  after  the  leaves  are  curled  it  is  impossi]:)le 
to  reach  them  with  the  spray  successfully.  Kerosene  emulsion 
*  C.  P.  Gillette,  Journal  of  Economic  Entomology,  Vol.  TIT.  p.  207. 


608        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

containing  7  per  cent  kerosene,  whale-oil  soap  1  pound  to  5  or  6 
gallons,  dilute  miscible  oils,  or  tobacco  extracts  will  destroy 
the  aphides.  The  spray  should  be  applied  with  some  force,  so  as 
to  hit  all  of  the  aphides  and  to  penetrate  the  hairy  terminals  of 
the  apple.  Where  trees  are  being  sprayed  with  Bordeaux  mixture, 
whale-oil  soap  or  tobacco  extracts  may  be  added  to  it,  to  save 
separate  spraying. 

The  Tent  Caterpillar  * 

From  the  earliest  times  the  webs  of  the. tent  caterpillar  have 
adorned  the  neglected,  wayside  apple  and  cherry  trees  in  all 
parts  of  the  country  east  of  th(^  Rocky  Mountains.  On  the 
Pacific  Coast  a  nearly  related  species  has  very  similar  hal)its.  The 
adult  moths  are  common  in  July  in  the  North  or  in  May  in  the' 
Gulf  States.  The}-  are  stout-bodied,  of  a  reddish-brown  color, 
with  two  nearly  parallel  white  bands  extending  obliquely  across 
the  fore- wings.  The  females  have  a  wing  expanse  of  aliout 
1^  inches,  while  the  males  are  smaller  and  may  be  distinguished 
by  their  feathery  antenna?.  The  sexes  soon  mate  and  the  females 
deposit  their  eggs  al^out  five  or  six  weeks  after  apples  blossom. 
The  egg-mass  is  from  one-half  to  three-quarters  inch  long  and 
forms  a  grayish-broWn,  knot-like  band  around  the  twig  on  which 
it  is  laid,  closely  resembling  the  bark  in  color.  Each  mass  con- 
tains about  200  eggs,  placed  on  end,  packed  closely  together  and 
covered  with  a  light-brown,  frothy  glue,  which  gives  a  tough, 
smooth,  glistening  surface  to  the  whole  mass.  The  little  cater- 
pillars hatch  just  as  the  leaf  buds  are  expanding  in  the  spring. 
Ofttimes  they  emerge  before  the  leaf  buds  have  expanded  suf- 
ficiently to  furnish  any  food,  in  which  case  they  satisfy  their 
hunger  with  the  glutinous  covering  of  the  egg-mass,  spinning  a 
thin  web  over  it.  Soon  they  are  able  to  bore  into  the  buds  and 
a  web  is  commenced  at  the  nearest  crotch.     Wild  cherry  and 

*  Malacasoma  americana  Fab.  Family  LasiocompidcE.  See  A.  L.  Quaint- 
ance,  Circular  98,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  V.  H.  Lowe, 
Bulletin  152,  N.  Y.  Agr.  Exp.  Sta.;  E.  P.  Felt,  14th  Report  State  Ent.  N.  Y., 
pp.  177-190. 


Fig.  459 


Fig.  460 


Fig.  461 


The  Tent  Cateri)illar. 


Fig.  462 


Fig.  459. — Egg  mass  on  twig — natural  size. 

Fig.  460. — Egg  mass  covered  with  web  of  newly-hatched  caterpillars. 

Fig.  461. — Newly-formed  web. 

Fig.  462. — Web  bearing  half-grown  caterpillars — reduced  in  size. 


600 


610        INSECT   PESTS   OF  FARM,   GARDEN   AND   ORCHARD 


apple  are  the  favorite  food-plants  and  are  often  stripped  of  their 
foliage  year  after  year,  but  all  of  the  common  fruit  trees  are  more 
or  less  frequented,  and  when  very  abundant  the  common  shade 
trees  are  attacked  and  occasionally  one  is  defoliated.  The 
little  caterpillars  from  one  egg-mass  co-operate  in  spinning  the 
tent  which  furnishes  them  shelter  at  night  and  during  cokl  or 
wet  weather.  This  is  gradually  enlarged  with  new  layers  of  silk, 
the  caterpillars  living  beneath  the  outer  layers.  The  caterpil- 
lars are  grown  in  five 
or  six  weeks,  when  they 
become  exceedingly 
restless  and  wander 
away  from  the  nest 
in  search  of  suitable 
places  for  spinning  their 
cocoons.  The  full- 
grown  caterpillar  is 
about  2  inches  long, 
deep  black  in  color, 
sparsely  covered  with 
yellowish  hairs,  with  a 
white  stripe  down  the 
middle  of  the  back.  On 
the  side  of  each  seg- 
ment is  an  oval  pale 
blue  spot  with  a  broader 
velvety  black  spot  ad- 
joining it  in  front,  giv- 
ing somewhat  the  effect 
of  an  eye-spot.  Having  found  a  suitable  place  under  loose 
bark,  in  a  fence,  in  the  grass  or  rubbish  beneath  the  tree, 
or  in  the  shelter  of  some  neighboring  building,  the  caterpillar 
settles  down  and  proceeds  to  encase  itself  in  a  thin  cocoon  of 
tough  white  silk,  in  which  it  transforms  to  the  pupa.  About 
three  weeks  later  the  adult  moth  emerges  from  the  pupa  to  con- 
tinue the  life  cycle,  there  being  but  one  generation  a  year. 


^ 

^              Wti'^L  ijF       T^^^Hfef 

k 

Co^vS^^H^^^^^^^I^Hn^i^         ' 

^vH^ffl^  ^ 

l|^^|^^;>i^ 

Fig.  463. — Tent  caterpillars  on  web — one- 
half  natural  size.     (Photo  by  Weed.) 


INSECTS    INJURIOUS  TO   THE  APPLE  AND  PEAR  611 

Tiic  ciiU'ipillars  arc  licitl  in  check  by  iiunicrou.s  parasitic 
insects,  some  21  species  having  been  fountl  preying  upon  them 
by  Mr.  W.  F.  Fi.skc  in  Xcw  Hampshire,*  as  well  as  l)y  })rc(hxceous 
soldier  bugs  {Podisus  spp.)  antl  many  of  our  common  birds. 
Large  numbers  of  the  caterpilhirs  are  also  carried  off  by  a  bacterial 
disease.  When  nearly  full  grown  the  caterpillars  Ijecome  sick 
antl  sluggish,  and  soon  become  flaccid  and  the  skin  is  easily 
ruptured,    permitting   the   escape   of   the   body   fluids.     Several 


Fig.  464. — Tont  caterpillars,  back  and  side  view — Ij  times  natural  size. 

species  of  little  chalcis-fiies  are  parasitic  in  the  eggs  and  destroy 
a  large  proportion  of  them.  Were  it  not  for  these  natural  enemies 
the  tent  caterpillar  would  become  a  much  more  serious  pest. 

Control. — The  egg-masses  may  easily  be  detected  and  pruned 
off  during  the  winter,  and  it  would  be  well  to  leave  them  in  a  box 
covered  with  netting  so  that  the  parasites  may  escape.  Neglected 
apple  and  wild-cherry  trees  should  be  destro}-ed.  as  they  harl^or 
this  and  other  pests  and  are  usually  valueless.  The  caterpillars 
may  be  quickly  destroyed  by  spraying  with  Paris  green  or  arsenate 
of  lead  just  after  the  foliage  comes  out,  before  the  trees  l^lossorr. 

*  See  W.  F.  Fiske,  Tech.  Bulletin  6,  N.  H.  Agr.  Exp.  Sta. 


Fig.  465. — The  tent  cateri)illar  moth.     (After  Lowe.) 


Fig.  466. — Cocoons  of  the  tent  caterpillar,     Fig.  467. — Web  of  the  tent  eater- 
natural  size,     (xlfter  Lowe.)  pillar  riddled  by  birds.     (Photo 

by  Weed.)  612 


INSECTS    INJURIOUS  TO  THE  APPLE    AND   PEAR 


613 


If  there  are  but  a  few  nests  the  caterpilhirs  may  be  destroyed 
in  them  by  spra3ang  the  nest  on  a  cloudy  or  cool  day  with  pure 
kerosene.  Apply  the  spray  with  an  extension  i-od  and  fine  nozzk^ 
so  that  the  nest  will  be  thoroughly  soaked,  without  spraying  the 
surrounding  foliage.  Or  the  caterpillars  ma}'  l)e  destroyc^d  Ijy  burn- 
ing the  nests  with  a  torch  while  they  are  in  them,  or  while  young 
they  may  be  swabbed  out  with  a  l)room  or  Ijrush  and  crushed. 


The  Yellow-necked  Apple  Caterpillar  * 

During  late  summer  the  tips  of  apple  limbs  are  often  found 
defoliated  for  a  foot  or 
two  and  if  examined  a 
mass  of  caterpillars  will  be 
found  huddled  together  as 
if  confessedly  guilty.  Usual- 
ly these  will  prove  to  be- 
long to  this  or  the  following 
species.  The  full-grown 
yellow-necked  apple  cater- 
pillar is  about  2  inches 
long,  with  a  jet  black  head 
and  the  next  segment, 
often  called  the  neck,  a 
bright  orange  yellow,  from 
which  the  insect  is  named. 
Down  the  middle  of  the 
back  runs  a  black  stripe, 
and  on  either  side  of  the 
body  are  three  stripes  of 
black  alternating  with  four 
of  yellow  and  the  body 
is  thinly  clothed  with 
long,      soft     white      hairs. 


Fig.  468. — Yellow-necked  apple  cate  •- 
pillar.s  assembled  on  apple  twig  in 
natural  position — from  life,  much 
reduced. 


*  Daiana  ministra  Drur^^  Family  Xotodontida;.  See  A.  S.  Packard, 
Memoirs  National  Academy  of  Sciences,  \o\.  VII,  p.  106;  E.  D.  Sanderson, 
Bulletin  139,  X.  H.  Agr.  Exp.  Sta.,  p.  213. 


614 


INSECT   PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


While  young  the  caterpillars  feed  only  on  the  under 
surfaces  of  the  leaves,  but  as  they  l^ecome  larger  the  whole  leaf, 
except  the  stem,  is  devoured.  They  feed  together  in  colonies, 
usually  starting  at  the  tip  of  a  limb,  where  the  eggs  were  laid, 
and  stripping  the  foliage  toward  the  base,  and  are  often  found 
clustered  together  in  a  solid  mass.  If  the  limb  is  jarred  or  a 
caterpillar  touched,  it  at  once  assumes  a  position  characteristic 
of  this  genus,  throwing  the  head  and  tail  in  the  air  with  a  jerk 

'  and  clinging  to  the  limb  by 
the  abdominal  prolegs,  as 
shown  in  Fig.  468.  The  wings 
of  the  adult  moth'  expand 
about  two  inches  and  are  a 
reddish-ljrown  color,  while  the 
head  and  thorax  are  chestnut 
brown.  The  fore-wings  have 
three  to  five  transverse  lines, 
one  or  two  spots,  and  the 
outer  margin  of  a  dark  color, 
and  the  hind-wings  are  pale 
ye'lowish  without  markings. 

Life  History.  —  Th(^  winter 
is  passed  in  the  pupal  stage 
in  the  soil,  from  which  the 
moths  emerge  from  May  to 
July.  The  round,  white  eggs 
are  laid  on  the  leaves  in  masses  of  75  to  100,  and  hatch  during 
mid-summer.  The  caterpillars  feed  during  the  late  summer  and 
become  full  grown  in  four  or  five  weeks,  when  they  enter  the 
earth  for  from  2  to  4  inches  and  there  transform  to  naked 
brown  pupae,  without  making  any  cocoons.  There  is  but  one 
generation  in  the  Northern  and  Middle  States. 

The  species  occurs  throughout  the  Northern  and  Middle  States 
east  of  the  Rocky  mountains,  and  in  the  far  South  there  seem  to 
be  no  records  of  the  species.  Though  most  common  on  apple,  it 
also   feeds  on  pear,   cherry,  cjuince,  and  plum,  and  on  hickory, 


Fig.  469. — The  yellow-necked  apple 
caterpillar  (Da/o«a  ministra  Dru.): 
mature  larva;  and  moth — natural  size. 


INSECTS    INJITRIOUS  TO   THE   APPLE    AND   PEAR 


615 


oak,  walnut,  chestnut  and  other  shade   and  forest  trees,  some- 
times   defoliating   them,   as   do   other  nearly  related    species. 

Control. — As  the  woi-k  of  these  caterpillars  is  soon  noticed, 
and  as  they  habitually  feed  in  colonies,  it  is  an  easy  matter  to 
hantl  pick  and  desti'oy  them,  or  swab  them  off  the  liml)s  with  a 
rag  or  wast(^  saturated  with  kei-osene,  or  where  a  colon}-  is  clustered 
at  the  tip  of  a  limb,  it  may  be  cut  off  and  crushed.  If  this  and 
other  caterpillars  are  abundant  on  the  foliage  in  late  summer, 
it  will  l)e  well  to  spray  with  arsenate  of  lead  3  pounds  to  the  barrel 
while  the  caterpillars  are  small,  which  will  be  about  six  to  eight 
weeks  after  the  apple  blossoms  fall. 

The  Red-humped  Apple  Caterpillar  * 

This  species  is  often  associated  with  the  preceding  in  very 
similar  injury,  and  has  pi-actically  the  same  habits.  The 
name  is  given  on  account  of 
the  prominent;  hump  on  the 
fourth  segment  of  the  larva, 
which  with  the  head  is  a  bright 
coral  red.  The  mature  catcr- 
piUar  is  striped  with  yellowish- 
white,  alternating  with  dark 
brown  or  Ijlackish  lines,  and  a 
double  row  of  black  spines  ex- 
tends along  the  back.  The  fore- 
wings  of  the  moth  expand  about 
1^  inches,  ire  dark  brown  on 
the  inner  and  grayish  on  the 
outer  margin;  they  have 
a  dark-brown  dot  near  the 
middle,  a  spot  near  each  angle, 
and  several  longitudinal  streaks 
of  the  samo  color  along  the 
posterior    margin.       The    hind- 


\ 

1- 

1 

1 

/ 

Fig.  470. — The  red-humped  apple 
caterpillar  {Schizura  concinna 
S.  &  A.) — slightly  enlarged. 


*  Schizura  concinna  Smith  and  Abbott.  Family  Notodontidoe.  See  A.  S. 
Packard,  Memoirs  National  Academy  of  Sciences,  Vol.  VII,  p.  212;  E.  D. 
Sanderson,  Bulletin  139,  N.  H.  Agr.  Exp.  Sta.,  p.  216. 


610 


INSECT  PESTS  OF  FARM,   GARDEN   AND  ORCHARD 


wings  of  the  male  are  Ijrownish  and  of  the  female  dusky 
brown,  the  l^ody  is  light  ]:)rown  with  the  thorax  of  a  darker  shade. 
This  species  occurs  thi-oughout  the  United  States  and  feeds  on 
apple,  plum,  rose,  thorn,  clieny,  l)lackberry,  willow,  oak,  hickory, 
and  other  trees  and  shrubs.  The  caterpillars  become  full  grown 
in  late  summer  or  early  fall  and  then  spin  loose  silken  cocoons  to 

^^•hich  are  attached  bits  of 
earth  and  rubl^ish,  so  that 
they  closely  resemble  their 
sui'roundings  as  they  lie 
on  the  ground  l^eneath 
rubbish,  or  just  under  the 
surface  of  the  soil.  After 
some  time  the  larva?  trans- 
form to  pupa,  in  which 
stage  the  winter  is  passed. 
Otherwise  the  life  History 
is  practically  the  same  as 
the  preceding  species,  ex- 
cept that  there  is  some 
evidence  of  there  being  two 
generations  in  the  South.  The  larva?  of  this  species  are  very 
frequently  parasitized  by  little  ichneumon-flies  *  which  destroy 
whole  colonies  of  them  while  still  young,  the  inflated  skins  being 
found  on  the  under  side  of  a  leaf,  often  perforated  by  the 
round  exit  holes  of  the  parasites. 

Control. — Same  as  for  the  preceding  species. 


Fig.   471. — Eggs     of    the  red-humped 
apple  caterpillar — enlarged. 


The  Apple  Leaf -miner  f 

This  is  the  most  common  leaf-miner  of  the  apple  and  makes 
small  brown  trumpet-shaped  blotches  under  the  upper  surfaces 


*  Limneria  fugitiva  Say,  and  L.  oedemasioe  Ashm.     Family  Ichneumonidoe. 

f  Tischeria  malifoliella  Clemens.  Family  Tineidce.  See  A.  L.  Quaintance, 
Bulletin  68,  Part  III,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  C.  D.  Jarvis, 
Bulletin  45,  Storrs  (Conn.)  Agr.  Exp.  Sta.;  C.  O.  Houghton,  Bulletin  87, 
Del.  Agr,  Exp.  Sta. 


INSECTS    INJURIOUS   TO   THE  APPLE    AND  PEAR  617 

of  the  leaves.  It  has  not  been  regarded  as  a  serious  pest  until 
recentlj-,  but  during  the  last  few  years  it  has  become  so  abundant 
as  to  do  serious  injury  to  apple  foliage  in  New  England  and  the 
Middle  Atlantic  States,  in  some  instances  largely  defoliating  the 
trees.  It  is  a  native  insect  which  is  generally  distributed  east  of 
the 'Rocky  Mountains. 

The  adult  is  a  little  moth  whose  wings  expand  about  one-third 
inch  and  are  broadly  fringed  as  shown  in  the  figure.  Clemens 
describes  it  as  follows:  "  Head  and  antenna?  shining  dark  brown, 
face  ochreous.  Fore-wings  uniform,  shining  dark  l)rown  with  a 
purplish  tinge,  slightly  dusted  with  pale  ochreous;    cilia  of  the 


Fig.  472. — Trumpet-shaped  mine  of  the  apple  leaf-miner  {Tischeria  malifo- 
liella  Clem.).     (Photo  by  Quaintance,  U.  S.  Dept.  Agr.) 

general  hue.  Hind-wings  dark  gra>-;  cilia' with  a  rufous  tinge." 
The  full-grown  larva  is  one-third  inch  long,  somewhat  flattened, 
and  tapers  from  the  broad  thorax  to  the  last  segment.  It  is 
light  green  except  the  back  of  the  prothorax  and  the  anal  seg- 
ment, which  are  Ijrown. 

Life  History. — The  moths  emerge  in  late  April  in  Delaware  and 
in  May  in  Connecticut.  The  small  greenish-yellow,  blister-like 
eggs  are  elliptical  in  outline,  about  one-fiftieth  inch  long,  and  are 
attached  closely  to  the  surface  of  the  leaf.  They  hatch  in  from 
eight  to  ten  days  and  the  young  larvie  mine  directly  into  the  leaf 
from  the  under  side  of  the  eggs.  The  larvae  become  full  grown  in 
about  three  weeks  and  pupate  in  their  mines,  the  pupal  stage 
lasting  eight  to  ten  days.     Thus  the  whole  life   cycle   requires 


618         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

but  about  thirty-three  days  in  the  District  of  Columbia,  where 
there  are  four  generations  a  year,  and  about  six  weeks  in  Con- 
necticut, where  there  are  but  two  generations.  The  laivto  of 
the  last  generation  line  their  mines  with  silk  and  in  them  pass  the 
winter  in  the  fallen  leaves,  transforming  to  pupa?  the  next  spring. 

Control. — As  the  larvae  pass  the  winter  in  the  fallen  leaves,  the 
insect  may  be  entirely  controlled  by  plowing  under  the  leaves 
in  late  fall  or  early  spring  or  by  raking  them  up  and  burning  them. 
When  the  larva?  become;  so  abundant  as  to  threaten  serious  injury 
in  summer  they  may  be  killed  in  their  mines  l)y  spr;n-ing  the 
foliage  with  10  to  15  per  cent  kerosene  emulsion,  l)ut  tliis  is 
not  satisfactorv  in  the  earlv  fall. 


The  Pistol  Case-bearer  *  and  the  Cigar  Case-bearer  f 

These  interesting  little  case-bearers  have  long  Ijeen  known  as 
apple  insects,  but  only  in  comparatively  recent  years  have  they 


Fig.  473. — The  pistol  case-bearer  (Coleophora  malivorella  Riley):  a,  ajjple 
twig  showing  larval  cases  and  work  on  leaves;  h,  larva;  c,  pupa;  d, 
moth;  h,  c,  d,  enlarged.     (After  Riley.) 

done  sufficient  injury  to  attract  attention.     Both  species  have 
done  serious  damage  in  New  York  by  boring  into  the  young  buds 

*  Coleophora  malivorella  Riley.  Family  Elachistidoe.  See  V.  H.  Lowe. 
Bulletin  122,  N.  Y.  Agr.  Exp.  Sta. 

t  Coleophora  fletcherelln  Femald.  Family  Elachutidce.  See  M.  V.  Slinger- 
land,  Bulletin  93,  Cornell  Univ.  Agr.  Exp.  Sta.;  A.  G.  Hammar,  BuUetiji  80, 
Part  II,  Bureau  of  Entomology,  U.S.  Dept.  Agr. 


INSECTS   INJURIOUS   TO   THE  APPLE   AND   PEAR 


()19 


and  blossoms,  and  eating  orf  the  surface  of  the  leaves,  so  that  in 
some  cases  orchards  have  been  practically  defoliated.  The  pistol 
case-bearer  seems  to  be  genei'ally  disti'ibuted  over  the  eastei'n 
United  States  and  southern  Canada,  while  the  cigar  case-lx^arer 
is  known  to  occur  in  Canada  from  Nova  Scotia  to  British 
Colunil)ia,  in  New  York,  Michigan,  Kansas  and  New  Mexico. 
As  both  insects  are  readily  carried  on  nurser}-  stock  the}-  are 
doubtless  much  more  widely  distributed  than  the  rcn-ords  indi- 
cate. 

Life  History. — The  life  histories  of  both  species  are  very  similar 


Fig.  474. — The  cigar  case-bearer  (Coleopfwra  fictcherella  Fernald):  a,  adult 
female;  b,  side  view  of  pupa  and  upper  view  of  cremaster  of  same; 
c,  larva;  d,  egg;  e,  venation  of  wings — much  enlarged.  (After  Hammar, 
U.  S.  Dept.  Agr.) 

and  have  been  most  interestingly  described  in  detail  by  the 
authors  cited.  The  young  caterpillars  hibernate  in  their  little 
cases,  which  are  attached  to  the  twigs  usually  near  or  upon  the 
buds. 

Those  of  the  pistol  case-bearer  are  about  one-eighth  inch  long 
and  resemble  the  bark  in  color.  A  short  time  befort^  the  leaf- 
luids  burst  in  the  spring,  the  larvie  become  active^  and  attack 
the  growing  buds,  gnawing  through  the  outer  cover  to  feed  on 
the  tender  tissues  beneath.  Later  they  feed  on  the  young 
leaves,  making  small  holes  through  the  surface  and  feeding  on 
the  soft  tissue  within  in  much  the  same  manner  as  a  true  leaf- 


620       INSECT   PESTS  OF   FARM,   GARDEN   AND   ORCHARD 


miner.  In  feeding  they  do  not  leave  the  case,  but  reach 
out  as  far  as  possible  from  it.  As  they  grow  they  enlarge 
their  cases,  which  finally  assume  the  shape  characteristic  of 
the  species. 

Those  of  the  cigar  case-bearer  are  straight  and  resemble 
a  miniature  cigar,  being  of  a  brown  color  and  composed  of 
bits  of  leaf  bound  together  with  silk.  The  cases  of  the  pistol 
case-bearer    resemble    an    old-fashioned  pistol  in  shape,  the  butt 

being  at  the  upper  end,  and 
are  blackish,  being  composed 
of  excrement  and  silk.  As 
the  caterpillars  become  larger 
the}"  devour  the  entire  leaf, 
except  the  midrib  and  large 
veins,  and  also  attack  the 
flower  buds,  flowers  and  fruit. 
The  larvcC  of  the  cigar  case- 
bearer  become  full  g  r  o  w  n 
about  the  middle  of  June  .'n 
New  York,  when  they  mi- 
grate to  the  twigs,  where  they 
attach  their  cases  firmly  to 
the  bark  and,  turning  around 
so  that  their  heads  are  out- 
ward, transform  to  pupae. 
The  pupal  stage  lasts  ten  or 
twelve  dayti,  most  of  the  moths  emerging  in  early  July.  The 
pistol  case-bearers  become  full  grown  and  transform  about  a 
month  earlier.  The  adults  of  both  species  are  little  grayish 
moths  with  wings  expanding  about  one-half  inch,  and  broadly 
fringed  with  long  hairs.  The  eggs  of  both  species  are  laid  singly 
on  the  under  sides  of  the  leaves  and  hatch  in  ten  days  to  two  weeks. 
The  young  caterpillars  which  hatch  from  them  feed  within  the 
leaf  for  a  short  time  as  leaf-miners,  before  they  make  their 
little  cases  and  migrate  to  the  twigs,  where  they  remain  until 
spring. 


Fig.  475. — The  cases  of  the  cigar 
case-bearer:  a,  upper  view  of  the 
cigar-shai)ed  case;  showing  the 
smooth  and  the  hairy  sides  and  the 
three-lobed  hind  opening;  b,  side 
view  of  same;  c,  the  case  as  it 
appears  in  the  spring  with  the  tube- 
like addition ;  d,  the  fall  and  winter 
case — much  enlarged.  (After  Ham- 
mar,  U.  S.  Dept.  Agr.) 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        621 


Fig.  476. — Apple  leaf  with  cigar  case-bearers  at  work — natural  size.    (After 
Hammar,  U.  S.  Dept.  Agr.) 

Control. — Spraying  with  Paris  green  or  arsenate  of  lead  just 
before  the  leaf  buds  open  and  again  as  sooti  as  the  foliage  is  out, 
will  destroy  the  little  caterpillars. 


The  Bud  Moth  * 

This  is  a  European  species  which  was  first  noted  in  this  countiy 
in  1841,  and  has  since  spread  throughout  the  Northern  and  Middle 
States  east  of  the  Rocky  Mountains  and  to  Oregon  and  Idaho. 
The  larvae  feed  on  all  of  the  common  deciduous  fruit  trees,  and 
blackberry,  but  are  most  commonly  injurious  to  apple.  The 
adult  moth  is  a  dark  ash  gray  with  broad  yellowish  bands  across 
the  fore-wings,  which  expand  about  five-eighths  inch.  The 
full-grown  caterpillar  is  one-half  inch  long,  of  a  light  chestnut- 

*  Tmetocera  ocellana  Schiff.  Family  Tortricidos.  See  M.  V.  Slingerland, 
Bulletin  107,  Cornell  Univ.  Agr.  Exp.  Sta.;  W.  E.Britton,  9th  Report,  State 
Entomologist  of  Connecticut,  p.  353. 


622        INSECT   PESTS  OF   FARM,  GARDEN   AND   ORCHARD 

brown  color,  with  the  head,  legs  and  thoracic  shield  dark  brown 

or  black,  smooth  and  shiny. 

Life  Histori/. — The  larva?  hibernate  in  small,  oval,  silken  cases 

attached  to  the  bark  of  a  twig.  About  the  time  the  l)uds  begin 
to  swell  in  the  spring,  the  caterpillars 
bore  into  them,  thus  early  protecting 
themselves  from  insecticides.  As  the 
young  leaves  and  flowers  unfold,  the 
caterpillars  form  nests  for  themselves 
l)y  tying  the  leaves  together,  and  de- 
stroy the  young  foliage  and  flower  buds, 
but  do  not  leave  the  nests  in  feeding. 
In    New  York,    they  become  full  grown 

during   June,    and   transform   to   pupae   in  the    silk-lined   nests. 

About    ten    days    later  the    moths    emerge   and  lay   the     eggs 

singly  or  in  small  clusters   on   the  under  surface   of  the  leaves. 


Fig.  477.— The  bud  moth 
(Tmetocera  o  cellana 
Schiff.) — twice  natural 
.size.  (After  W.  E. 
Britton.) 


Fig.   478. — Young   apple  leaves   infested   by   the  bud  moth  larva.     (After 

V.'.  E.  Britton.) 

The  egg  is  disk-like,  much  flattened,  usually  oval  in  shape, 
and  transparent,  reseml:»ling  a  minute  drop  of  water.  The 
eggs  soon  hatch   and   the  \'oung  caterpillars   feed   on   the  under 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR       623 


sides  of  the  leaves,  protecting  tiiemselves  by  a  thin  silken 
web.  In  the  fall  they  migrate  to  the  twigs  and  form  the  small 
silken  cases  in  which  they  pass  th(>  winter. 

Control. — Dr.    Brittoii    icjhjiIs   that    the   caterpillars   may   be 


Fig.  479. — Apple   loaf  injured    by  the  bud   moth  caterpillar — natural   «ize. 
(After  W.  E.  Britton.) 

effectively  destroyed  by  spraying  with  arsenate  of  lead  1  pound 
to  10  gallons,  which  should  be  applied  just  as  the  buds  are  bursting 
and  again  before  the  trees  blossom. 


624         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Codling  Moth  * 

The  common  apple  worm,  the  larva  of  the  codling  moth,  is 
probably  the  best  known  and  most  generally  destructive  of  all 
the  apple  insects.  It  is  an  old  European  insect  and  has  been 
distributed  to  almost  all  parts  of  the  world  where  apples  are 


Fig.  480. — The  codling  moth  {Cydia  pomondla  Linn.):  a,  egg — greatly 
enlarged;  h,  young  larva  hatching  from  egg;  c,  larva  in  winter  cocoon 
on  inside  of  a  bit  of  bark;  d,  pupa — original;  e,  moth — after  Slinger- 
land — all  much  enlarged. 

grown.  The  "  wormy  "  apple  is  so  well  known  that  the  work 
of  the  larva  needs  no  description,  but  the  aggregate  loss  which 
it  occasions  is  not  always  appreciated,   as  most  of  the  injured 

*  Cydia  pomonella  Linn.  Family  Tortricidce.  See  A.  L.  Quaintance, 
Yearbook  U.  S.  Dept.  Agr.,  1907,  p.  435;  E.  L.  Jenne,  Bulletin  80,  Part  L 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  C.  B.  Simpson,  Bulletin  41,  n.  s., 
Div.  Ent.,  U.  S.  Dept".  Agr.;  E.  D.  Sanderson,  Bulletin  143,  N.  H.  Agr.  Exp. 
St'a.;  and  bulletins  of  the  State  Agrcultural  Experiment  Stations. 


INSECTS  INJURIOUS  TO  THE  APPLE   AND  PEAR 


625 


fruit  drops  and  no  account  is  kept  of  the  windfalls,  and  if  the  picked 
fruit  is  not  seriously  infested  the  grower  does  not  notice  that  he 
has  lost  a  large  part  of  the  ci'op,  though  where  the  p(>st  is  abundant 
so  much  of  the" fruit  is  injured  that  hut  little  remains  to  l)e  picked 
on  unsprayed  trees.  In  1907  Professor  Quaintance  estimated 
the  annual  loss  tlue  to  this 
insect  in  the  United  States  at 
about  $12,000,000. 

The  moths  fly  at  dusk  and 
are  rarely  seen,  as  during  the 
day  they  rest  on  the  bark 
which  they  closely  reseml)le 
in  color.  The  wings  expand 
about  three-quarters  inch  and 
have  somewhat  the  appear- 
ance of  grayish-brown  watered 
silk,  but  when  more  closely 
examined  are  seen  to  be 
crossed  by  numerous  lines  of 
gray  and  brown  scales.  Near 
the  hind  angle  of  each  front 
wing  is  a  large  dark  brown 
spot  marked  with  streaks  of 
brown  or  gold.  The  hind- 
wings  are  of  a  lighter  grayish- 
brown  color,  darker  toward 
the  outer  margin. 

L'fe  History. — The  winter  is  passed  by  the  full-grown  larvae  in 
their  small  white  cocoons  beneath  or  in  crevices  of  the  bark. 
About  the  time  the  apples  blossom  the  larvte  transform  to  small 
brown  pupse,  from  which  the  moths  emerge  in  two  to  three  weeks. 
If  the  evenings  be  warm  the  females  commence  to  deposit  their 
eggs  within  a  few  days,  laying  most  of  them  on  the  foliage.  A 
female  lays  from  60  to  75  eggs,  and  though  most  of  them  are 
placed  on  leaves  near  the  young  fruit,  ofttimes  they  are  deposited 
on  limbs  or  trees  with  no  fruit.     The  individual  egg  looks  much 


Fig.  481. — Cocoons  of  codling  moth  as 
found  attached  to  a  piece  of  loose 
bark — natural  size.  (After  Slinger- 
land.) 


626 


INSECT  VESTS  OF   FARM,  GARDEN  AND  ORCHARD 


like  a  small  white  blistcu'  about  the  size  of  a  pinhead.  It  is  at 
first  quite  transparent,  but  later  a  brownish  or  blackish  streak 
is  seen,  showing  the  little  caterpillar  forming  within.  The  eggs 
hatch  in  from  five  to  ten  (la3's,  depending  upon  the  season  and 
temperature,  most  of  them  hatching  about  three  or  four  weeks 
after  the  blossoms  fall. 

The  young  apple  worm  is  at  first  only  about  one-sixteenth 
inch  long,  of  a  whitish  color,  with  a  shining  black  head,  and 
with  distinct  l^lackish  tubercles  over  the  body,  which  become 
quite  indistinct  in  later  life.  Upon  hatching  the  young  larva 
usually  feeds  a  little  on  the  tender  parts  of  the  leaves  before 
it    crawls    to    the    nearest    apple,    which    is    prolial)ly    8    or    10 


Fig.  482. — Fupsc  of  codling  moth  in  cocoons — enlarged.      (After  Slingerland.) 

inches  distant.  About  two-thirds  of  the  larviu  enter  the  apples 
through  the  blossom  end  and  feed  a  little  within  the  calyx  before 
they  bore  inward  to  the  core.  The  others  enter  at  the  stem  end 
or  at  the  side,  where  a  leaf  may  touch  the  apple.  The  seeds  of 
the  apple  seem  to  be  most  relished,  for  the  larva  soon  hollows 
out  each  of  them  as  well  as  the  surrounding  core,  its  work  being 
indicated  by  the  well-known  excreta  thrown  out  from  the  calyx, 
showing  the  ''  worminess  "  of  the  apple.  The  larva  becomes  full 
grown  in  from  three  to  four  weeks  and  eats  its  way  out  through 
the  side  of  the  apple,  leaving  a  round  exit  hole,  and  seeks  a  place 
to  form  its  cocoon.  The  full-grown  caterpillar  is  about  three- 
quarters  inch  long,  whitish  or  pinkish  in  color,  with  a  brown  head 


INSECTS  INJURIOUS  TO  THE  APPLE  AND   PEAR       627 


and  faint  tubercles  over  the  Dody,  and  with  three  pairs  of  thoracic 

legs  and  five  pairs  of  abdominal  prolegs.     The  cocoons  arc  found 

mostly   on   the   trunks   of   tlu^   trees,   as   in   winter.     The   pupal 

stage  of  the  first  sunnuer  gen- 
eration   lasts    ten    to    twelve 

days,  and  the  moths  emerge 

about  eight  weeks    after   the 

eggs  were  laid. 

In   northern   New   England 

but    2    or  3   per  cent   of  the 

larvic    pupate,    the  majority 

hilxM-nating    over    winter,  so 

that    tliere     is     but    a   small 

second    generation.      Further 

south   a  large   number  trans- 
form and  in  the  Middle  States 

there  are  two  full  generations. 

In  the  far  South,  as  in  Georgia, 

Arkansas    and    New   Mexico, 

there    are    three    generations 

In  an}'  event  the  larvae  leave  the  apples  in  the  fall  and  hib(M-. 

nate    in    tluur    cocoons,  those    but    partly  grown    usually  d}'ing 

befoi'e  spring.  The  life  cycle 
of  the  second  and  third  gen- 
erations are  essentially  the 
same  as  that  of  the  first, 
except  that  a  large  propor- 
tion of  the  eggs  are  laid  on 
the  fruit  and  more  of  the  lar- 
vte  enter  the  apples  through 
the  sides  or  stem  end.  The 
work  of  the  larva  of  the 
later  broods  is  also  some- 
M'hat    different,  as  much  of 

it  consists  of  eating  around  the  blossom  end   or    on    the    face 

of    the    apple,    eating   out   small  holes   or    tunneling  under   the 


Fig.  483. — Pupa  skin  of  codling  mpth 
remaining  attached  to  cocoon — en- 
larged. *^  I 


Fig.  484. — Young  larva  of  codling  moth 
in  calyx  cavity  of  apple— enlarged. 


628       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


skin,  as  shown  in  Fig.  489,  When  two  or  three  generations 
occur,  the  injury  by  them  often  becoms  very  severe  if  the 
first  generation  has  not  been  largely  destroyed  by  thorough 
spra5dng.     Very  similar  injury  is  done  l)y  the  larva  of  the  lesser 

apple  worm,*  which  is  very  difficult  to 
distinguish,  but  fortunately  the  same 
treatment  will  control  both  pests. 

Control. — Scraping  the  loose  bark  from 
the  trees  and  keeping  the  bark  smooth 
removes  the  favorable  conditions  for  the 
hil)ernation  of  the  larvae.  A  large  pro- 
portion of  the  hibernating  larvse  are 
destroyed  by  woodpeckers  and  nut- 
hatches during  the  winter  and  they 
should  be  attracted  to  the  orchards 
by  hanging  up  bones  and  suet.  Pick- 
ing up  the  fallen  apples  and  destroying 
them  before  the  larvae  have  left  them  to 
form  their  cocoons  will  do  much  to 
mitigate  the  numbers  and  will  aid  in 
the  control  of  other  insects.  Cellars  and 
storage  houses  where  apples  are  kept 
over  winter  should  l^e  screened  to  pre- 
vent the  exit  of  the  moths  in  the  spring. 
The  principal  method  of  control,  how- 
ever, is  in  spraying  with  arsenicals, 
which,  when  properly  done,  will  destroy 
practically  all  of  the  larvse.  Although  Paris  green  and  arsenitc 
of  lime  (p.  43)  have  long  been  used  for  this  purpose,  arsenate  of 
lead  is  now  preferred  on  account  of  its  superior  adhesive  qualities 
and  because  there  is  less  danger  of  burning  the  foliage  with  it. 
Where  Bordeaux  mixture  is  sprayed  for  fungous  diseases  at  the 
same  time  Paris  green  may  be  applied  with  it  and  the  Bordeaux 


Fig.  485. — Larva  of  the 
codling  moth  only  a 
few  (lays  old,  showing 
tubercles  —  much  en- 
larged. (After  Slinger- 
land.) 


*  Enarmonia  prunivora  Walsh.  Family  TortricidcB.  See  A.  L.  Quaintance. 
Bulletin  68,  Part  V,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  Foster  and 
Jones,  Bulletin  80,  Part  III,  ibid. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR 


629 


will  cause  it  to  adhere  as  well  as  arsenate  of  lead  and  there  will  be 
little  danger  of  burning  with  a  good  quality  of  Paris  green.  One- 
third  pound  per  ])arrel  of  Paris  green,  2  or  3  pounds  of  arsenate  of 
lead,  or  1  (juart  of  stock  solution  of  arsenite  of  lime  are  the  proper 
strengths  for  g(>nei-al  use.  The  fii-st  spraying  for  the  codling  moth 
should  l)e  given  just  after  the  blossoms  liave  fallen  and  l)eforo 
the  sepals  of  the  calyx  close,  the  object  being  to  place  the  poison 
in  the  calyx  cavity  so  that  the  little  larva  will  be  poisoned  when  it 
enters  and  feeds  in  the  calyx  a  few  weeks  later.     In  general  this 


Fig.  4S6.-;-Fu11  grown  larva  of  the  codling  moth — enlarged  about  tliree 
times.     (After  Slingerland.) 

spraying  should  be  given  within  a  week  or  ten  daj-s  after  two- 
thirds  of  the  petals  have  dropped,  but  the  time  will  depend  upon 
the  variety  and  the  season. 

In  the  West  great  emphasis  has  recently  been  placed  upon 
using  a  coarse  spray  with  a  high  pressure,  100  to  250  pounds, 
w^hich  will  drive  the  spray  through  the  bases  of  the  stamens 
into  the  lower  calyx  cavity,  and  though  excellent  result  are 
undoubtedly  secured  in  this  way,  experiments  in  the  East 
indicate  that  a  mist  spray  is  equally  effective  if  thoroughly 
applied,  whether  the  lower  calyx  cavity  is  reached  or  not. 
There  is  no  question,  however,  of  the  importance  of  maintaining 


630        INSECT   PESTS  OF  FARM,   GARDEN   AND  ORCHARD 

a  good  pressure,  of  at  least  100  pounds,  so  that  the  spray  maybe 
forced  through  the  f ohage ;  for  the  1  )lossoms  point  in  all  directions^ 
and  the  spray  must  be  forced  through  the  tree  to  reach  those  point- 
ing inward  on  the  opposite  side.  To  do  thorough  work  the  man 
spraying  should  stand  on  a  tower  which  will  place  him  level  with 
the  middle  of  the  tree,  so  that  with  an  extension  rod  all  parts  may 
be  readily  reached.     An  angle  on  the  end  of  the  rod  which  will 


Fig.  487. — Young  apples  in  right  condition  to  spray  for  the  codling  moth 
and  with  calj'x  sepals  closed  too  far  for  effective  spraying.  (Afier 
Quaintance,  U.  S.  Dept.  Agr.) 

turn  the  nozzle  at  35  or  45  degrees  will  greatl}-  aid  in  jcacliing 
all  parts  of  the  tree. 

The  second  spraying  should  be  ajDplicd  three  or  four 
weeks  after  the  blossoms  fall,  just  as  the  eggs  are  hatching 
At  this  time  the  object  should  be  to  cover  the  foliage  thor- 
oughly, so  that  the  young  larvae  may  be  killed  while  they  feed 
on  the  foliage.  Consequently  both  the  upper  and  under  surfaces 
of  the  leaves  should  be  coated.  If  the  first  spraj'ing  has  b(>en  well 
done,  the  second  will  often  be  unnecessary  where  ther(>  is  but 
a  partial  second  brood  or  where  the  pest  is  well  under  control, 
but  as  it  is  often  necessary  to  spray  for  the  fungous  diseases 


INSECTS   INJURIOUS   TO   THE  APPLE  AND   PEAR        631 


at  this  time  it  is  well  to  add  the  arsenical,  which  but  slightly 
increases  the  cost.  Where  there  is  a  full  second  generation,  as 
in  most  of  the  Middle  and  Pacific   States,  a  third  application  as 


't--..,. 


Fig.  488. — Work  of  the  first  generation  of  codling  moth  larvae. 

the  second  generation  of  larvie  are  hatching,  will  be  found  advis- 
able about  nine  or  ten  weeks  after  the  petals  fall,  and  a  fourth 
two  or  three  weeks  later  may  be  necessary.     With  thorough  spray- 


FiG.  489. — Work  of  the  second  generation  of  codhng  moth  hirvse. 

ing  not  over  1  or  2  per  cent  of  the  picked  fruit  shoidd  be  wormy, 
as  most  of  the  wormy  fruit  will  drop  early  in  the  season. 

In  mountainous  districts,  or  where  it  is  difficult  to  secure  water, 
dusting  the  trees  with  Paris  green  blown  by  a  dusting  machine 
has  been  quite  extensively  practiced.      Although  this  treatment 


G32        INSECT  PESTS  OF   FARM,  GARDEN  AND   ORCHARD 

largely  reduces  the  injury,  careful  experiments  have  shown  that 
it  is  much  less  effective  than  liquid  spraying,  and  as  it  is  not 
satis"actory  or  the  control  of  fungous  diseases,  the  liquid  spray- 
ing is  to  be  preferred  where  feasible. 

The  Apple-maggot  or  "  Railroad  Worm  "  * 

The  apple-maggot  has  long  been  known  as  the  worst  pest  of 
summer  and  fall  apples  in  the  New  England  States,  and  has 
extended  its  injuries  to  eastern  New  York  and  southeastern 
Canada.  It  has  been  recorded  from  Michigan,  Wisconsin,  Illinois, 
Minnesota,  New  Jersey,  and  Pennsylvania,  but  seems  to  be  only 
occasionally  injurious  there,  though  it  has  been  reared  from  haws 
in  Illinois  and  Wisconsin,  which  would  indicate  that  the  insect 
is  native  in  those  States.  Evidently  it  is  widely  distributed 
throughout  the  northeastern  United  States,  but  for  some  reason 
is  most  injurious  in  New  England.  The  fruit  is  injured  by  the 
small  white  maggots,  which  burrow  through  the  flesh,  leaving 
discolored  streaks  through  it,  often  becoming  so  numerous  as  to 
entirely  hone^'comb  the  pulp  which  breaks  down  into  a  yellowish 
mass  merely  held  together  by  the  skin.  An  apple  quite  fair 
exteriorly  will  often  be  found  to  be  almost  completely  ''  rail- 
roaded "  by  the  maggots,  although  brown,  slightly  sunken 
streaks  in  the  skin  usually  indicate  their  presence.  Sweet  and 
subacid  varieties  of  summer  and  early  fall  apples  are  worst  injured, 
but  where  the  pest  develops  unchecked,  winter  sorts,  such  as  the 
Baldwin  and  particularly  the  Northern  Spy,  are  often  seriously 
injured. 

The  parent  of  the  maggot  is  a  little  fly  slightly  smaller  than 
th(>  house-fly"  of  a  blackish  color,  with  j^ellowish  head  and  legs, 
greenish  eyes,  and  three  or  four  white  bands  across  the  abdomen. 
The  wings  are  marked  by  four  black  Ijands,  as  shown  in  Fig.  490, 
which  distinguish  it  from  similar  flies  found  on  apples. 

*  Rhagoletis  pomonella  Walsh.  Family  Trypetidce.  See  A.  L.  Quaintance, 
Circular  101,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  F.  L.  Harvey,  Report 
Maine  Agr.  Exp.  Sta.,  1889,  p.  190;  W.  C.  O'Kane,  Journal  of  Economic 
Entomology,  IV,  173. 


INSECTS  INJURIOUS  TO   THE  APPLE  AND  PEAR 


633 


Life  History. — The  flies  emerge  during  July  in  New  England 
and  live  for  several  weeks.  The  females  at  once  commence 
depositing  their  eggs  in  the  early  varieties  of  apples.  The  eggs 
are  laid  just  under  the  skin  in  a  vertical  position,  on  the  cheek  of 
the  apple.  The  egg  is  elliptical,  about  one-thirtieth  inch  long, 
and  yellowish  in  color.  A  female  will  lay  300  to  400  eggs,  12 
or  15  often  being  placed  in  a  single  apple.  The  eggs  hatch  in 
four  or  five  days  and  the  little  maggots  at  once  burrow  into  the 
pulp.  By  means  of  a  vertical  motion  of  the  head  they  rasp  the 
pulp  with  the  small,  black  hook-like  mouth  parts,  and  in  less  than 


Fig.  490. — The  apple-maggot  (Rhagoletis  pomonella  Walsh):  a,  adult;  h, 
larva  or  maggot;  c,  funnel  of  spiracle  on  head;  d,  puparium;  e,  portion 
of  apple  showing  injury  by  maggots;  a,  b,  d — enlarged;  e — reduced. 
(After  Quaintance,  U.  S.  Dept.  Agr.) 

a  minute  can  tunnel  their  own  length.  They  become  full  grown 
in  four  to  six  weeks  during  the  summer,  but  if  only  partly  grown 
when  winter  sets  in,  many  of  them  seem  to  hibernate  until  spring. 
The  mature  maggot  is  about  one-third  inch  long,  }'cllowi.sh-white, 
footless,  much  like  similar  maggots,  and  distinguishable  by  the 
microscopic  characters  of  the  spiracles  of  the  first  and  last  seg- 
ments. The  mature  maggot  goes  just  beneath  the  surface  of  the 
ground,  where  its  skin  hardens  to  a  puparium  in  which  the  pupa 
is  formed,  in  which  stage  the  winter  is  passed.  In  barrels  or 
storage  places  the  maggots  pupate  beneath  the  apples,  and 
occasionally  a  puparium  is  found  in  the  burrow  of  the  maggot 


634        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 


within  an  api^le.     Most  of  the  puparia  are  within  1  or  2  inches  of 
the  surface.     There  is  but  one  generation  a  year. 

Control. — As  most  of  the  affected  fruit  drops  to  the  ground, 
during  summer  it  should  be  picked  up  twice  a  week  and  destroyed 
before  the  maggots  have  left  to  it  pupate.  Where  this  is  carefully 
done  injury  by  the  pest  is  greatly  reduced.  Particular  attention 
should  be  given  to  the  destruction  of  infested  summer  apples. 
Hogs  pastured  in  the  orchard  will  do  this  work  admirably,  and 
where  there  are  but  a  few  trees  on  bare  or  cultivated  ground 
chickens  will  destroy  the  larva?.  Plowing  the  orchard  deeply 
as  early  as  feasible  in  spring  and  keeping  it  well  cultivated  in  early 
summer  will  bury  the  puparia  so  as  to  greatly  lessen  injury,  which 
is  always  worse  in  uncultivated  sod  orchards.  As  yet  no  method 
of  spraying  has  been  used  which  shows  any  effect  on  this  pest, 
as  the  maggots  inside  the  apple  cannot  be  reached  by  a  spray, 
but  experiments  are  now  being  made  in  New  Hampshire  which 
may  show  a  method  of  killing  the  adidt  flies,  as  has  been  done  with 
a  similar  pest  in  the  orchards  in  South  Africa. 

The  Apple  Curculio  * 

The  apple  curculio  has  been  commonly  confused  with  the  plum 
curculio  (p.  576),  but  is  by  no  means  as  .common  or  injurious,  and 


Fig.  491. — The  apple    curculio  (Anthoitonius   quadrigibbus  Say):    a,  b,  adult 
beetles;  c,  larva;  d,  pupa — all  enlarged.     (After  Riley.) 

is  quite  distinct  in  both  appearance  and  habits.     The  adult  beetle 

is  about  the  same  size  as  the  plum  curculio,  but  more  reddish- 

*  AjUhononnis  quadrigibbus  Say.  Family  Curculionidce.  See  C.  S. 
Crandall,  Bulletin  98,  111.  Agr.  Exp.  Sta.,  p.  514;  F.  E.  Brooks,  Bulletin  126, 
W.  Va.  Agr.  Exp.  Sta.,  p.  113. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND   PEAR 


635 


brown  in  color,  tho  abdomen  is  more  robust,  and  the  wing-covers 
bear  four  proniincnit  humps,  the  anterior  being  much  larger  than 
those  on  the  pktm  curcuho.  The  snout  of  the  apple  curculio  is 
as  long  as  the  rest  of  the  body  and  is  held  straight  forward  from 
the  head,  instead  of  hanging 
down  as  does  the  snout  of  the 
plum  curculio.  The  work  of 
the  apple  curculio  is  also  differ- 
ent in  that  after  laying  the 
egg  in  a  small  cavity  in  the 
fruit,  no  crescent-shaped  mark 
is  made  around  it.  The  apple 
curculio  is  a  native  species 
which  breeds  in  wild  haw, 
wild  crab,  and  wild  cherry, 
and  has  been  reared  in  plum, 
quince  and  pear.  "  It  has 
been  reported  from  Connecti- 
cut and  Ontario  south  to 
North  Carolina  and  westward 
as  far  as  New  Mexico.  It 
seems  to  have  been  more 
troublesome  in  Missouri,  Illi- 
nois and  other  mid-western 
States  than  elsewhere,"  but 
has  never  clone  anything  like 
the  injury  due  to  the  plum 
curculio  and  can  hardly  he 
regarded  as  a  serious  pest. 

Life  History. —  The  beetles 
commence  laying  eggs  in  the 
fruit  soon  after  the  blossoms  drop  and  continue  for  a  period  of  sixty 
days,  an  individual  female  laying  about  65  eggs.  The  eggs  hatch 
in  about  five  days  and  the  larvae  feed  on  the  flesh  of  the  apple 
for  about  twenty  days,  when  they  transform  to  pupa?  within  the 
fruit.     A  week  later  the  beetles  emerge,  but  feed  very  little  during 


Fig.  492. — Work  of  the  apple  curculio; 
a,  a',  c,  c',  feeding  punctures  from 
the  surface  and  in  section;  b,  b',  egg 
punctures  from  the  surface  and  in 
section.     (After  C.  S.  Crandall.) 


636      INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

the  late  summer  before  they  enter  hibernation  for  the  winter, 
most  of  them  leaving  the  trees  by  the  latter  part  of  August. 

The  larva  is  a  footless,  whitish  grub  a  half  inch  long  when  full 
grown  with  a  hump-backed  appearance  due  to  the  enlargement 
of  the  anterior  abdominal  segments,  which  prevents  the  larva 
from  straightening  out.  The  beetles  injure  the  fruit  l;)y  puncturing 
it  for  feeding  and  for  the  deposition  of  eggs,  causing  it  to  become 
dimpled  and  gnarled  as  does  the  plum  curculio,  and  the  larva)  feed 
within  the  fruit,  mining  the  flesh,  in  which  they  imdergo  their 
complete  development. 

Control. — Thickets  of  wild  crab  or  hawthorn  trees  should  be 
destroyed  wherever  near  an  orchard,  for  the  beetles  will  breed  in 
their  fruit  and  then  migrate  to  the  orchard.  Jarring  as  for  the 
plum  curculio  may  be  practiced  on  young  trees,  and  spraying  as 
for  that  species  will  doul)tless  largely  reduce  the  injur}'.  Usually 
this  insect  is  not  sufficiently  injurious  to  warrant  special  treatment 
where  its  native  food-plants  arc  not  overal^undant  near  the 
orchard. 

The  Pear  Leaf  Blister-mite  * 

The  pear  leaf  blister-mite  has  long  been  known  as  a  pest  of  pear 
foliage  wherever  the  pear  is  grown,  and  has  similarly  affected  apple 
foliage  in  Europe,  but  only  in  recent  years  has  it  become  a  serious 
pest  of  apple  foliage  in  New  York,  New  England,  Ontario  and 
Pennsylvania.  Just  why  it  should  suddenly  become  an  apple 
pest  after  having  occurred  in  this  country  for  years  without 
noticeably  injuring  it  is  a  mystery,  though  diy  seasons  may 
possibly  be  accountable  for  it. 

The  work  of  the  mites  is  recognized  by  reddish  blisters  forriiing 
on  the  young  foliage,  which  later  turn  ])lackish  and  have  a  corky 
texture.  Badly  affected  leaves  drop,  so  that  a  tree  is  often  largely 
defoliated,  and  where  the  mites  are  abundant  they  attack  the 
young  fruit. 

*  Eriophyes  pyri  Pgst.  Class  Arachnida.  Order  Acarina.  Family 
Eriophyidce,  with  which  are  associated  several  nearly  related  species  -with 
similar  habits.  See  Parrott,  Hodgkiss  and  Schoene,  Bulletins  283  and  306, 
N.  Y.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS   TO  THE  APPLE  AND  Pl'^AR         637 

The  mites  are  not  true  insects,  as  they  belong  to  the  same  class 
as  the  spiders,  scorpions,  and  ticks.  One  of  the  more  common 
larger  mites  is  the  red  spider  of  greenhouses,  which  affects  flower- 
ing plants,  vegetable  crops,  antl  fruits  of  all  sorts.  These  little 
blistcr-mitcs  are  of  microscopic  size,  only  1/100  to  1/200  inch  in 
length,  so  that  they  can  only  be  seen  with  a  lens,  and  must  l)e 
examined  with  a  compound  microscope  to  distinguish  the  species. 
One  is  shown  much  magnified  in  Fig.  493.  They  are  elongate, 
with  two  pairs  of  legs,  and  slender  abdomens,  composed  of  50 
to  SO  small  rings,  frequently  marked  with  rows  of  small  tubei'clcs 
and  ornamented  with  a  few  hairs  and  bristles. 

Life  History. — The  mites  spend  the  winter  in  the  buds,  and 


Fig.  493. — The  pear  leaf  blister-mite  (Eriophyes  pyri  Pgst.):   highly  magni- 
fied.    (After  Parrot t.) 

as  warm  weather  approaches  in  the  spring  the}'  Ix'come  active 
and  move  toward  the  base  of  the  growing  bud  scales  and  feed 
there.  As  the  young  leaves  unfold  the  mites  migrate  to  them. 
They  burrow  through  the  surface  of  the  leaf  and  feed  upon  the 
succulent  tissue  within,  setting  up  an  irritation  which  soon  results 
in  reddish  spots  on  the  surface.  Within  these  mines  the  eggs 
are  laid,  as  many  as  14  having  been  found  in  a  single  blister. 
The  young  hatch  in  about  a  week  and  burrow  around  in  all 
directions,  feeding  on  the  tissues  and  juices.  When  full  grown 
they  leave  the  gall  through  small  openings  in  the  under  surface 
and  start  new  colonies  which  produce  similar  galls.  They  con- 
tinue to  reproduce  and  migrate  throughout  the  summer,  and  under 
favorable    conditions   become    numerous   enough    to    completely 


638      INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 

infest  the  new  leaves  as  they  appear.     In  the  fall  they  leave  the 
leaves  to  hibernate  in  the  buds  as  already  described. 

On  pear  the  blisters  are  at  first  greenish  pimples,  which  l^ecome 
reddish  and  later  brilliant  red  blisters,  and  finally  they  become 
brown   or   black   and   the   tissue   corky.     When  numerous  the 


Fig.  494. — Old  leaf  cluster  with  galls  of  pear  leaf  blister-mite  on  apple  fruit 
and  leaves.     (After  Parrott,  Hodgkiss  and  Schoene.) 

galls  coalesce,  forming  dark  brown  patches  over  the  leaf,  which 
often  break  open,  particularly  along  the  edges  of  the  leaves. 
On  the  blossom  ends  of  the  fruit  and  on  the  stems  they  produce 
light-colored  pimples,  which  do  not  seem  to  injure  the  fruit. 
On  apple  the  blisters  are  less  brilliantly  colored  than  on  pear, 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        039 

and  become  a  light  brown  or  dark  green  color  on  the  upper  leaf 
surface  and  uniformly  brown  beneath,  looking  something  like 
the  work  of  the  ap{)le  rust.  Tiie  young  fruit  is  sometimes  attacked^ 
on  which  small  green  pimples,  which  later  make  blister-like  spots 
or  pock  marks,  are  made  toward  the  blossom  ends,  but  which 
do  not  seem  to  cause  much  damage. 

Control. — The  mites  may  be  controlled  by  spraying  with 
10  per  cent  kerosene  emulsion,  miscible  oils,  or  lime-sulfur  wash 
used  the  same  as  for  the  San  Jose  scale.  Spraying  should  be 
done  in  October  or  November  as  soon  as  possible  after  a  majority 
of  the  leaves  have  fallen,  as  many  of  the  mites  are  still  in  the 
pubescence  of  the  young  wood,  where  they  are  more  easily  de- 
stroyed than  when  under  the  bud  scales.  In  spring  spray  just 
as  the  buds  begin  to  break  and  show  the  tips  of  the  young  leaves; 
spraying  later  than  this  will  injure  the  foliage,  and  earlier  spraying 
is  not  as  effective.  By  using  lime-sulfur  in  the  spring,  the  usual 
treatment  with  Bordeaux  mixture  for  diseases  at  that  time  is 
unnecessary.  Where  infestation  is  serious  both  fall  and  spring 
sprayings  should  be  given;  otherwise  the  fall  spra3'ing  is  the 
better.  The  liuds  and  new  growth  should  be  thoroughly  drenched, 
while  the  rough  bark  of  the  trunk  and  old  limbs  may  be  neglected 
as  far  as  the  mites  are  concerned.  Where  pear  trees  are  but 
slightly  infested,  the  spread  of  the  pest  may  often  be  prevented 
by  simply  pruning  out  and  burning  the  infested  twigs  upon  the 
first  appearance  of  injur}-. 

The  Pear  Psylla  * 

Where  the  pear  psylla  is  abundant,  pear  growers  have  come 
to  fear  it  next  to  the  San  Jose  scale,  and  until  recently  owners 
in  eastern  New  York  became  so  discouraged  in  their  attempt  to 
control  it  that  orchards  were  cut  down.  It  is  an  old  European 
pest  and  was  first  noted  in  Connecticut  in  1S32,  since  when  it  has 
spread  southward  to  Maryland  and  ^"irginia  and  westward  to 

*  Psylla  pyricola  Foerst.  Family  Psyllidoe.  See  M.  V.  Slingerland, 
Bulletins  44  and  108,  Cornell  Univ.  Agr.  Exp.  Sta.;  C.  L.  Marlatt,  Circular 
7,  Div.  Ent.,  U.  S.  Dept.  Agr. 


640 


INSECT  PESTS  OF  FARM,  GARDEN  AND   ORCHARD 


Michigan  and  Illinois,  in  which  States  it  has  done  considerable 
injury.  The  psyllas  are  nearly  related  to  the  plant-lice  and  are 
sometimes  called  jumping  plant-lice,  on  account  of  the  habit  of 
the  adults  of  giving  a  quick  jump  and  fl}'ing  from  the  foliage 
when  disturbed.  Like  the  plant-lice  they  reproduce  very  rapidly 
and  suck  the  juices  from  the  foliage  and  fruit.  Usually  the  first 
indication  of  the  pest  is  the  presence  of  large  quantities  of  honey- 
dew,  secreted  by  the  nymphs,  with  which  the  foliage  becomes 
covered,  and  which  attracts  numerous  ants.  When  the  psjdlas 
are  numerous  the  leaves  and  fruit  become  coated  with  this  sticky 


Fig.  495. — The  pear  psylla  [Paylla  pyricola  Foerst):  adult,  full-grown  nymph 
and  egg — all  greatly  enlarged  in  different  proportions.  (After  Slinger- 
land.) 

substance  and  it  even  drops  from  them  like  rain  and  runs  down 
the  trunk.  A  blackish  fungus  grows  on  the  honey-dew  and  is 
always  a  good  indication  of  the  presence  of  the  psylla. 

Badly  infested  trees  are  so  injured  by  loss  of  sap  that  they 
shed  their  leaves  in  midsummer,  the  lower  ones  l)e;ng  the  first 
to  turn  yellow  and  drop.  The  young  fruit  also  drop  from  badly 
infested  trees,  which  make  but  little  growth,  as  the  young  shoots 
are  often  attacked  and  wither  early  in  the  season. 

The  adult  psjdla  is  about  one-tenth  inch  long,  of  a  reddish- 
crimson  color  with  brownish-black  markings,  bronzy  eyes  and 
dark  wing-veins,  looking  very  much  like  a  miniature  cicada  or 
dog-day  harvest-fly. 


INSECTS  INJURIOUS  TO  THE  APPLE   AND   PEAR        641 

Life  Historij. — The  atlults  liibernate  over  winter  in  crevices 
of  the  bark  and  there  lay  their  eggs  late  in  April  or  early  May 
on  the  twigs  or  around  the  buds.  The  egg  is  about  one- 
eighteenth  inch  long,  hardly  perceptible  without  a  lens,  and 
orange-yellow  in  color.  It  is  pear-shaped  with  the  small  end 
ilrawn  out  into  a  long  thread,  and  the  larger  end  is  attached  to 
the  l^ark  by  a  short  stalk  (Fig.  495).  The  later  generations 
deposit  the  eggs  on  the  leaves  often  in  rows  or  bunches.  The  eggs 
hatch  in  two  to  three  weeks  and  the  young  nymphs  feed  on  the 
leaf  petioles  in  the  axils  of  the  leaves  and  later  on  the,  leaves, 
^•oimg  fruit  and  tender  shoots,  from  which  they  suck  the  sap. 
The  nymph  is  a  peculiar-looking  little  bug,  broadly  oval,  flattened, 
of  a  yellowish  color,  with  crimson  eyes,  but  later  becomes  reddish 
with  black  markings  and  conspicuous  black  wing-pads,  as  shown 
in  Fig.  495.  They  move  very  slowly  and  are  frequently  quite 
covered  by  their  own  honey-dew.  After  molting  some  four  or 
five  times,  they  finally  transform  to  adults  in  about  a  month. 
According  to  Slingerland  there  ai^e  four  generations  in  New  York 
and  probably  five  in  Maryland. 

Control. — As  the  adults  hibernate  over  winter  in  the  bark 
the  treatment  advised  for  the  pear  leaf  blister-mite  furnishes  the 
best  means  of  control  for  the  psylla,  and  winter  treatment  is 
absolute!}'  essential  for  its  successful  control.  Otherwise,  the 
best  time  to  spray  is  in  the  spring  just  after  the  eggs  have  hatched 
and  before  the  nymphs  have  secreted  much  honey-dew.  If 
winter  or  spring  spraying  has  been  neglected,  the  trees  should  be 
thoroughly  sprayed  with  whale-oil  soap,  1  pound  to  4  gallons, 
or  10  per  cent  kerosene  emulsion,  or  dilute  miscibleoils.  Spraying 
should  be  done  after  a  shower,  which  wall  wash  much  of  the  honey- 
dew  off,  as  the  chief  difficulty  in  summer  spraying  is  to  reach  the 
nymphs  through  the  thick  coating  of  honey-dew  with  which  thev 
are  covered.  Obviously  the  spray  should  be  applied  with  ?on 
siderable  pressure  in  a  coarse  spray. 


642        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

The  Pear  Slug  * 

Not  infrequontly  the  foliage  of  pear  and  cherry,  and  occasionally 
of  plum,  trees  turns  ])rown  in  midsummer,  which  is  found  to  ho  due 
to  small,  slimy,  slug-like  larvic  which  have  eaten  off  the  surfaces 
of  the  leaves.  The  Pear  Slug  is  a  common  pest  throughout  the 
country,  having  been  known  here  for  over  a  century.  It  is  an 
old  European  pest  and  has  become  distributed  to  many  of  the 


Fig.  496. — The  pear  slug  (Eriocampoides  limacina  Retz.):  a,  adult  female 
saw-fly;  b,  larva  with  slime  removed;  c,  same  in  normal  state;  (/,  leaves 
with  larva} — natural  size;  a,  b,  c,  much  enlarged.  (After  Marlatt, 
U.  S.  Dept.  Agr.) 

British  colonies  in  various  parts  of  the  world.  The  parent  insect 
is  a  small  saw-fly,  about  one-fifth  inch  long,  glossy  black,  with 
four  wings  which  are  iridescent,  with  a  smoky  band  across  the 
middle,  and  which  are  folded  over  the  back  when  at  rest. 

Life  History. — The  flies  are  abroad  by  the  time  the  foliage  is 
well  out,  by  the  middle  of  April  in  Maryland  and  late  May  or  early 
June  in  New  England.  Like  most  of  the  saw-flies  the  female  is 
furnished  with   a  strong  ovipositor  with  saw-like  teeth   at  the 

*  Eriocampoides  limacina  Retzius.  Family  Tenthredinidce.  See  C.  L. 
Marlatt,  Circular  26,  Div.  Ent.,  U.  S.  Dept.  Agr. 


INSECTS  INJURIOUS  TO  THE  APPLE  AND  PEAR        643 

tip,  with  which  she  cuts  a  little  blister-like  cell  beneath  the  upper 
surface  of  the  leaf,  in  which  the  egg  is  deposited,  as  shown  in  Fig. 
497.  The  egg  hatches  in  about  two  weeks  and  the  little  larva 
makes  its  way  out  of  the  cell  t)ii-ough  a  crescent-shaped  cut. 

The  young  larva  is  at  fii-st  nearly  white,  except  the  yellowish- 
brown  heatl,  but  very  soon  a  slimy  or  gluey  olive-colored  litjuid 
exudes  from  over  the  entire  body,  giving  it  the  appearance  of  a 
minute  slug,  from  which  it  gets  its  name.  The  head  is  now  dark 
brown,  appearing  almost  black  under  the  slime,  and  the  body  is 
also  darker.  The  anterior  segments  are  much  swollen,  concealing 
the  head  and  the  thoracic  leos.     The  abdomen'  is  fui'nished  with 


Fig.  497. — Illustrating  method  of  ovijiosilion  and  emergence  of  the  pear 
slug:  a,  cutting  of  cell  beneath  epidermis,  showing  the  tip  of  the  ovi- 
positor; b,  the  cell  after  the  egg  has  been  deposited;  c,  same  after 
escape  of  the  larva — all  much  enlarged.     (After  Marlatt  U.S.  Dept.  Agr.) 

seven  pairs  of  prolegs,  the  usual  pair  on  the  last  segment  being 
wanting  so  that  the  tip  of  the  abdomen  is  slightly  elevated.  The 
little  slugs  commence  eating  out  small  bits  of  the  upper  surface 
of  the  leaf,  which  they  gradually  enlarge  until  nearly  the  whole 
upper  surface  is  denuded,  leaving  merely  a  network  of  veins, 
held  together  by  the  brown  epidermis  of  the  lower  surface,  which 
is  nearly  intact.  Leaves  thus  injured  turn  brown,  die  and  drop 
so  that  a  tree  will  sometimes  be  nearly  defoliated,  except  for  the 
new  growth  which  starts  out.  The  larvae  grow  rapidly,  becoming 
full  grown  in  about  twenty-five  days,  when  they  are  about  one- 


644        INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

half  inch  long.  When  full  grown  the  larva  molts  for  the  fifth 
time  and  loses  its  olive-green  slimy  appearance,  becoming  a 
light  orange-yellow  color,  clean  and  dry,  with  a  light-colored 
head  marked  by  only  the  small  circular  black  eye-spots  on  the 
sides. 

The  larva  now  enters  the  ground  for  an  inch  or  twa,  where 
it  forms  a  small  cell,  which  is  moistened  with  saliva  so  that  the 
walls  become  somewhat  impervious  to  water.  In  six  or  eight 
days  it  transforms  to  the  pupa  and  in  about  two  weeks  after 
the  larva  entered  the  ground  the  adult  fly  digs  its  way  out  of 
the  soil.  Some  of  the  larvae  of  each  generation,  and  all  of  those 
of  the  last  generation  remain  in  the  soil  over  winter  and  trans- 
form to  pupae  the  next  spring.  At  Washington,  D.  C,  the  first 
generation  of  larva;  disappear  by  the  end  of  June  and  the  second 
generation  are  most  abundant  in  early  July,  when  the  principal 
injury  is  done,  which  is  probabl}^  followed  by  a  third  generation. 
Further  north  there  are  but  two  generations,  the  second  appearing 
in  August. 

CoJitroI. — By  spraying  with  any  of  the  arsenicals  when  the 
work  of  the  slugs  is  first  noticed  on  the  foliage  the}-  niay  be 
quickly  destroyed.  Whale-oil  soap,  or  other  soap,  1  pound  to 
4  gallons,  will  also  destroy  the  larva;  as  a  contact  insecticide. 
Hellebore,  air-slaked  lime,  or  almost  any  finely  divided  dust, 
thoroughh'  dusted  over  the  trees  will  also  destroy  most  of  the 
larva',  which  are  very  readily  killed.  In  gardens  where  water 
under  pressure  is  available,  the  slugs  may  be  washed  off  by  a  jet 
from  a  hose,  as  the}-  are  frequently  washed  off  by  heavy  rains, 
and  are  much  less  injurious  in  wet  seasons. 


CHAPTER  XXVIII 

INSECTS  IXJURIOUS  TO  THE  PEACH,  PLUM,  CHERRY  AND  STONE 

FRUITS  * 

The  Peach  Borer  f 

Wherever  peaches  are  grown  they  are  subject  to  the  attacks 
of  the  ever-present  borers,  and  if  neglected  will,  soon  siiccuml) 
to  their  injury.  East  of  the  Rocky  Mountains  the  common  peach- 
tree  borer  has  been  known  since  the  earliest  settlements,  and  it 
also  occurs  in  Colorado  and  Oregon.  It  is  a  native  insect  which 
probably  lived  on  wild  cherry  and  wild  plum,  and  is  known  to 
attack  plum,  prune,  apricot  and  nectarine,  though  chiefly  a 
peach  pest.  On  the  Pacific  Coast  a  nearly  related  species,  the 
California  peach-tree  borer, |  does  similar  injury  and  has  very 
similar  habits.  The  lesser  peach  borer  §  is  commonly  associated 
with  the  common  peach  borer  and  has  done  considerable  injury 
in  western  New  York,  Maryland,  Virginia  and  Georgia.  It  occurs 
throughout  the  country  and  is  doubtless  commonly  confused  Avith 
the  larger  and  more  common  species.  Although  it  is  quite  different 
in  its  life  history  and  habits,  the  injury  is  very  similar,  and  as  it 
must  be  controlled  by  the  same  methods  it  need  not  be  separately 
considered. 

The  presence  of  the  borers  may  be  detected  by  the  mass  of 
gummy,  gelatinous  material,  more  or  less  mixed  with  soil,  which 

*  See  J.  B.  Smith,  Bulletin  235,  N.  J.  Agr.  Exp.  Sta. 

t  Sanninoidea  exitwsa  Say.  Family  Sesiidw.  ■  See  Quaintance,  Yearbook 
U.  S.  Dept.  Agr..  1905,  p.  330;  M.  V.  Slingerland,  Bulletin  176,  Cornell  Univ. 
Agr.  Exp.  Sta.;  H.  N.  Starnes,  Bulletin  73,  Geo.  Agr.  Exp.  Sta. 

X  Sanninoidea  opalescens  Hy.  Ed.  See  C.  W.  Woodworth,  Bulletin  143, 
Cal.  Agr.  Exp.  Sta. 

§  Synanthedon  pictipes  G.  &  R.  See  A.  A.  Girault,  Bulletin  G8,  Part 
IV,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 

645 


646       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

exudes  from  the  crowns  of  trees  injured  by  them.  The  injury 
is  done  by  the  larvse  feeding  on  the  soft  inner  bark  of  the  crown 
of  the  root,  the  adjacent  roots  and  the  base  of  the  trunk.  Often 
the  larvse  will  completely  girdle  a  tree  and  where  a  tree  is  infested 
by  several  borers,  the  foliage  turns  yellow  and  if  not  treated  will 
soon  die.  Such  a  tree  is  much  more  susceptible  to  the  attacks 
of  bark  beetles  and  diseases.     Probably  as  many  peach  trees 


Fig.  498. — Peach  borer  moths  (Sanninoidea  exitiosa  Say) — natural  size. 
The  upper  one  and  the  one  at  right  are  females,  the  other  two  males. 
(After  Slingerland.) 

are  lost  from  the  work  of  borers  as  from  any  other  one  pest,  with 
the  possible  exception  of  the  San  Jose  scale. 

The  adults  are  clear-winged  moths  which  fly  during  the  day 
and  might  be  readily  mistaken  for  wasps.  The  females  are  a 
deep  steel-blue  with  a  l)road  orange  band  across  the  al)domen. 
The  fore-wings  arc  opaque,  covered  by  the  Ijluish  scales,  and 
expand  about  1{  inches,  while  the  hind-wings  are  transparent 
except  the  dark  margin.     The  males  are  smaller,  with  the  wings 


INSECTS  INJURIOUS  TO  STONE  FRUITS 


647 


clear  except  the  margins  and  a  line    across  the  fore-wings,  and 
the  abdomen  is  marked  with  three  or  four  narrow  yellow  stripes. 

Life  History. — The  moths  emerge  in  New  York  and  New  Jersey 
from  the  middle  of  Jul}-  to  the  latter  part  of  August,  at  Wash- 
ington, D.  C.  from  the  middle  of  June  until  mid-September, 
the  majority  emerging  in  late  July,  while  in  Georgia  the  majority 
emerge  in  late  August  and  early  September.  As  there  is  but  one 
generation  a  year,  the  time  of  emer- 
gence in  these  different  latitudes  is 
decidedl}-  anomalous  when  compared 
with  the  life  liistoric^s  of  other  insects. 
The  females  soon  lay  their  eggs,  pre- 
ferring to  place  them  on  the  base  of 
the  trunk,  but  often  placing  them 
higher,  or  even  on  weeds  or  trash, 
or  on  the  soil.  A  single  female  may 
lay  from  200  to  800  eggs.  The  eggs 
are  about  one  -fiftieth  inch  long,  and 
slightly  over  half  as  wide,  truncate 
at  one  end,  and  a  light  chestnut  brown 
or  reddish-brown  in  color,  not  easih' 
seen  on  the  bark  of  the  tree.  The}- 
hatch  in  about  ten  days  and  the 
young  larvffi  at  once  seek  out  small 
cracks  in  the  bark  through  which  they 
enter  the  soft  bark  of  the  tree.  Their 
presence  may  be  easily  detected  by 
the  powdery,  brownish  frass  which 
they  throw  out  of  their  Ijurrows.  The 
young  larvse  grow  rapidl}-  and  con- 
tinue feeding  until  forced  into  hibernation  by  cold  weather, 
and  in  the  South  doubtless  feed  during  warm  days  in  the  winter. 
Feeding  is  resumed  in  the  spring,  the  larvse  boring  through  the 
lower  layers  of  the  bark  and  causing  masses  of  gum  to  exude  as 
already  described.  Larvse  of  almost  all  sizes  may  usually  be  found 
in  late  spring,  and  the  resulting  moths  appear  irregularly  over 


Fig.  499.  —  Eggs  of  the 
peach  borer :  natural  size 
at  n ;  an  egg  gi-eat  ly  en- 
larged at  I;  and  end  of 
egg  greatly  magnified, 
showing  micropyle  at  ?«. 
(After  Slingerland.) 


648       INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

a  period  of  two  to  three  months.  It  seems  probable  that  some 
of  the  larvae  which  hatch  from  eggs  in  late  summer  or  early  fall, 
do  not  become  moths  until  the  second  sul)sequent  season,  so 
that  they  live  in  parts  of  three  years,  though  the  life  cycle  may 
occupy  two  years.  The  full-grown  borer  is  a  light  yellowish 
larva  about  1  inch  long,  with  a  brown  head  and  thoracic  legs, 
and  five  pairs  of  prolegs  on  the  abdomen.  The  body  is 
sparsely  clothed  with  brownish  hairs  which  arise  from  small, 
smooth  tubercles.  The  grown  larva  constructs  a  cocoon  at  or 
near  the  surface  of  the  ground,  usually  on  the  trunk  near  the 


Fig.    500. — The    peach    borer    larva,    natural    size    and    enlarged. 

.  Slingerland.) 


(After 


burrow,  but  often  on  the  soil,  which  is  composed  of  particles 
of  excrement  and  bark,  bound  together  with  gaim  and  a  thin 
lining  of  silk.  In  this  it  transforms  to  a  brown  pupa  from  which 
the  moth  emerges  in  about  three  weeks. 

Control. — One  of  the  best  means  of  preventing  injury  and 
making  the  removal  of  the  borers  easier  is  to  mound  the  soil 
around  the  trunk  as  high  as  possible,  just  before  the  moths  emerge 
in  the  summer.  This  forces  them  to  lay  their  eggs  high  up  on  the 
trunk,  where  the  little  borers  may  later  be  readily  found.  In  some 
way  this  mounding  seems  to  prevent  the  establishment  of  the 
young  larva?,  as  several  experimenters  have  found  that  from  half 


INSECTS  INJURIOUS  TO  STONE  FRUITS 


649 


to  three-fourths  of  the  borers  are  kept  out  of  the  trees  in  this 
way.  In  the  early  fall  the  earth  should  be  leveled  down  to 
facilitate  finding  the  little  larvie.  Oviposition  on  the  lower 
trunk  may  also  be  prevented  by  wrapping  the  trunk  with  building 
paper,  or  any  heavy  paper,  which  should  extend  well  into  the  soil 
below  and  be  tied  tightly  just  below  the  crotch  at  the  top.  Such 
wrapping  may  be  used  to 
advantage  with  the  niound- 
ing  up  of  the  earth  and 
thus  largely  prevent  ovi- 
position. The  wrappers 
should  be  applied  before  the 
moths  appear  and  be  re- 
moved in  the  early  fall. 
Various  washes  composed 
of  soaps,  lime,  glue,  cement, 
carbolic  acid,  and  various 
other  ingredients  have  been 
commonly  recommended 
and  widely  used  for  pre- 
venting the  laying  of  the 
eggs  and  the  entrance  of 
the  young  larva,  but  care- 
ful tests  have  failed  to 
show  their  value.  Doubt- 
less this  is  due  to  the 
roughness  of  the  bark  of 
the  peach,  over  which  it  is 
difficult  to  make  a  com- 
plete coating,  and  the  little 
larvse  will  enter  through  the 

smallest  crevice.  Some  wash  which  would  penetrate  the  burrows 
of  the  young  larvae  and  destroy  them,  as  does  the  avenarius  car- 
bolineum  with  the  bark  beetles  (p.  546),  would  seem  to  be  the 
most  promising  line  of  treatment,  and  some  of  the  washes  which 
have  been  extensively  used  by  practical  growers  shovdd  be  critically 


Fiti.  501. — Work  of  a  single  peach 
borer,  natural  size:  tr,  b,  burrow  of 
borer;  g,  gummy  mass;  /),  \ni\rd  project- 
ing from  cocoon.     (After  Slingerland.) 


650      INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 

tested  on  a  commercial  scale.  After  reducing  the  number  of 
borers  by  mounding  and  wrapping  the  grower  must  resort  to 
the  old-fashioned  method  of  "  worming  "  the  trees,  by  digging 
them  out  by  hand.  This  should  be  done  in  the  fall  and  again  in 
late  spring.  Professor  Starnes  strongly  recommends  that  in 
Georgia  the  chief  dependence  be  placed  upon  the  fall  worming, 
as  most  of  the  young  larvae  are  then  found  upon  the  surface  bark 
of  the  tree,  more  or  less  involved  in  a  mass  of  gum  and  excreta, 
with  which  they  may  be  readily  scraped  from  the  tree,  according 
to  his  ol)servations.  For  this  work  he  recommends  a  small 
curved  steel  blade  or  hook  about  4  or  o  inches  long  inserted  in 
a  wooden  handle  a  foot  in  length.  In  the  North  fall  worming 
seems  to  be  less  satisfactory.  For  spring  work  in  excavating 
the  larger  worms,  a  sharp  knife  and  a  stout  wire  are  commonl}' 
used,  although  many  prefer  a  blacksmith's  hoof-knife  or  similar 
tools  which  arc  specially  constructed  for  the  work. 

The  Peach  Twig-borer  * 

On  the  Pacific  Coast  the  Peach  Twig-borer,  often  known  there 
as  the  peach  worm,  is  one  of  the  most  serious  pests  of  the  peach. 
In  the  Eastern  States  it  has  been  injurious  in  Delaware,  Virginia 
and  Maryland,  but  only  occasionally.  Probably  the  insect  occurs 
throughout  the  country  wherever  the  peach  is  grown,  as  it  is 
an  old  European  insect  which  was  first  noticed  in  the  United 
States  in  1S60.  On  the  Pacific  Coast  the  over-wintering  larvae 
bore  into  the  tender  shoots  in  early  spring  and  during  the  summer 
bore  into  the  fruit,  particularly  the  later  varieties.  Prune,  nec- 
tarine, apricot,  almond,  and  pear  are  also  injured. 

The  adult  moth  is  a  dark-gray  color,  with  fore-wings  expanding 
about  one-half  inch  and  marked  with  darker  spots.  The  full 
grown  larva  is  about  one-half  inch  long,  of  a  dvdl  reddish-brown 
color  with  dark  brown  or  blackish  head. 

lAfe  History. — "  The  insect  passes  the  winter  as  a  very  small 

*  Anarsia  Uneatella  Zell.  Family  Geleckiidce.  See  W.  T.  Clarke,  Bulletin 
144,  Cal,  Agr.  Exp.  Sta.;  C.  L.  Marlatt,  Bulletin  10,  n.  s.,  Div.  Ent.,  U.  S. 
Dept.  Agr.;  A.  L.  Quaintance,  Yearbook  U.  S,  Dept.  Agr.,  1905,  p.  344. 


INSECTS  INJURIOUS  TO  STONE   FRl  ITS 


651 


larva  in  silken-lined  cells  or  burrows  in  the  spongy  tissue  of  the 
bark  at  the  crotches  of  the  limbs.  Their  presence  is  indicated 
by  small  mounds  of  comminuted  bark,  as  shown  in  Fig.  503,  at  a 
and  b.  Early  in  the  spring,  as  the  foliage  is  putting  out,  the 
larvEB  begin  to  leave  their  burrows  and  attack  the  tender  shoots, 
boring  into  and  down  the  pith,  the  galleries  ranging  from  about 
one-third  inch  to  Ih  inches  in  length.  The  shoot  thus  injured 
soon  wilts  and  dies,  as  shown  in  Fig.  504,  at  a.  Many  shoots  may 
be  attacked  by  a  single  lai'wa 
which  is  thus  capable  of  doing 
considerable  harm.  There  arc 
two  or  three  generations  of 
larvae  during  the  summer  in 
the  West,  those  of  the  second 
and  third  attacking  the  fruit, 
the  later  varieties  l^eing  the 
worst  injured.  According  to 
Professor  C.  V.  Piper,  the 
larva  enters  the  peach  at  the 
stem  end,  usually  boring  into 
the  pit,  the  seed  of  which  it 
seems  to  prefer,  usually  caus- 
ing the  stone  to  split  as  the 
fruit  ripens;  or  simply  the 
flesh  may  be  tunnelled,  de- 
pending on  whether  or  not 
the  stone  is  hard  when  the  fruit  is  attacked.  In  California, 
according  to  Clarke,  the  larva  usually  enters  the  fruit  along  the 
suture  at  the  stem  end,  and  excavates  a  chamber  beneath  the 
skin,  which  blackens  and  shrivels  somewhat,  affording  entrance 
to  organisms  of  decay.  In  the  ripe  fruit  the  larvic  fre- 
quently make  their  way  to  and  around  the  stone,  which, 
if  split,  may  be  entered  and  the  seed  fed  upon.  .  .  .  Early 
in  the  fall,  about  September  1,  in  California,  the  very  young 
larvae  from  eggs  of  the  last  generation  of  moths  construct 
their  hibernation  cells    in  the    soft    tissue   of    the   crotches   of 


—   The     peacTi     twig-borer 

{Anarsia  linealella)  :  adult  moth 
with  wings  spread  and  folded  — 
much  enlarged.  (After  Marlatt,  U. 
S.  Dept.  Agi-.) 


652 


INSECT  PESTS  OF  FARM,   GARDEN  AND  ORCHARD 


limbs,    where    they    remain    until    the    following    spring,    thus 

spending  some  six  months  in 
this  condition." — Quaintance. 
Control. — By  spraying  dur- 
ing the  winter,  or  preferably 
after  the  buds  have  swollen 
in  the  spring  with  kerosene 
or  distillate-oil  emulsion,  the 
oil  is  absorbed  by  the  cast- 
ings   at    the    mouth    of    the 

^  T^     ,        .    ,  .       .  burrows    of    the    hibernating 

Fig.  503. — Peach  twig-borer  in  winter 

quarters:   a,  twig,  showing  in  crotch  larva?,    and     thus    penetrates 

minute  masses  of  chewed  bark  above  the     burrow\s     and     kills     the 

larval  chamber;    h,  same,  much    en-  ,  ^  .  .,  , 

larged;   c,  larval  cell  enlarged;   and  ^arvse.      Lime-sulfur  wash,  ap- 

d,  larva  very  greatly  enlarged.    (After  plied  from  the  time  the  buds 

Marlatt,  U.  S.  Dept.  Agr.)  ,  „  , -,    ,i 

'  commence  to  swell   until  the 

first  blossoms,  has  also  been  wadely  and  successfully  used. 
The  wash  should  be  ap- 
plied as  late  as  possible 
before  blossoming.  Recently 
Mr.  E.  P.  Taylor  has  shown  * 
that  in  western  Colorado 
the  larvae  are  veiy  readily 
killed  by  arsenate  of  lead, 
3  to  5  pounds  per  barrel, 
applied  just  as  the  buds 
are  beginning  to  open.  The 
arsenate  of  lead  must  con- 
tain no  soluble  arsenic,  or 
it  may  burn  the  foliage. 
This  treatment  is  given  at 
the  same  season  as  the 
lime-sulfur  wash  and  is 
much  easier  to  prepare  and  appl}' 


Fig.  504. —  The  peach  twig-borer:  o, 
new  shoot  of  peach  withering  from 
attacks  of  larva;;  h,  larva  enlarged; 
c,  pupa,  enlarged.  (After  Marlatt, 
U.  S.  Dept.  Agr.) 


*E.  P.  Taylor,  Bulletin  119,  Colo.  Agr.  Exp.  Sta.,  p.  S. 


INSECTS  INJURIOUS  TO  STONE  FRUITS  053 


The  Peach-tree  Bark-beetle  * 

The  peach-tree  bark-beetle  is  very  simihir  in  both  appearance 
and  habits  to  the  fruit-tree  bark-beetle  (consult  p.  545),  and  may 
be  readily  confused  witli  it.  It  is  a  native  insect  which  attacks 
only  peach,  cherr}'  and  wild  cherry,  and  so  far  has  lieen  injurious 
only  in  western  New  York,  northern  Ohio,  and  the  Niagara  dis- 
trict of  Ontario,  though  it  occurs  from  New  Hampshire  to  North 
Carolina  and  west  to  Michigan. 

''  When  the  beetles  are  present  in  large  numl)ers  their  injuiy 
to  the  tree  is  quickly  brought  to  the  attention  of  the  orchardist 
by  the  large  amount  of  sap  exuding  from  the  trees  through  the 
many  small  borings  made  both  in  the  trunk  and  limbs  of  the 
tree.  .  .  .  The  adults  or  beetles  produce  the  primary  injury  to  healthy 
trees,  the  work  of  the  larvse  being  secondary.  The  healthy  trees, 
by  repeated  attacks  of  the  adults,  are  reduced  to  a  condition 
favorable  to  the  formation  of  egg-burrows.  When  the  beetles 
are  ready  to  hibernate  in  the  fall  they  fly  to  the  healthy  trees  and 
form  their  hibernation  cells.  These  latter  are  injurious  to  the 
trees,  for  through  each  cell  there  will  be  a  tiny  flow  of  sap  during 
the  following  season."  When  the  beetles  emerge  in  the  spring 
they  bore  into  the  bark  of  healthy  trees  and  later  leave  them  to 
form  egg  iDurrows  in  sickly  trees.  From  these  numerous  Ijurrows 
the  sap  issues  in  large  quantities  and  in  many  cases  forms  large 
gummy  masses  around  the  trees.  After  three  or  four  years  of 
such  injury  the  tree  is  so  weakened  that  the  beetles  form  their 
egg  borrows  beneath  the  bark  and  the  larvse  soon  finish  its 
destruction.  There  are  two  generations  a  year,  the  summer  brood 
appearing  in  the  last  half  of  August  and  the  other  hibernating 
over  winter. 

Control. — The  same  methods  are  advised  as  for  the  fruit-tree 
bark-beetle,  which  see  (p.  546). 

*  Phlosotribus  liminaris  Harris.     Family  Scolytidoe.     See   H.   F.   Wilson, 
Bulletin  68,  Part  IX,  Bureau  of  Entomology,  U.  S.  Dept.  Agr. 


654      INSECT  PESTS  OP  PARM,  GARDEN  AND  ORCHARD       ^ 

The  Peach  Lecanium* 

The  presence  of  the  "  terrapin  scale,"  as  this  species  is  often 
called,  is  usually  indicated  by  the  sooty  appearance  of  the  branches 
and  foliage  of  affected  trees.  This  is  due  to  the  fact  that  the 
scales  excrete  considerable  honey-dew,  which  covers  the  bark  and 
leaves,  and  on  which  a  sooty  fungus  propagates.  It  is  a  common 
species  throughout  the  eastern  United  States  and  also  attacks 
the  apple,  maple,  sycamore,  Hnden  and  birch,  but  is  most  injurious 
to  peach  and  plum.     The  hibernating,  partly  grown,  female  scale 


Fig.  505. — The  peach  lecanium  or  terrapin  scale  {Eulecanium  nigrofasciatum 
Pergande):  adults  at  left,  natural  size  and  much  enlarged;  young  at 
right,  and  unfertilized  female  at  center — much  enlarged.  (After  Howard, 
U.  S.  Dept.  Agr.) 

found  on  the  bark  in  winter,  is  about  one-twelfth  inch  long, 
hemispherical,  and  of  a  reddish  color  mottled  with  radiating 
streaks  of  black,  particularly  about  the  margin.  Sometimes 
these  streaks  coalesce  and  form  a  dark  band  around  the  center, 
while  other  individuals  are  occasionally  entirely  red  or  black. 
Frequently  trees  become  badly  encrusted  with  these  scales,  but 
rarely  are  they  killed  by  them.     The  fruit  on  badly  infested 

*  Eulecanium  nigrofasciatum.  Pergande.  Family  Coccidm.  See  J.  G. 
Sanders,  Circular  88,  Bureau  of  Entomology,  U.  S.  Dept.  Agr.;  A.  L.  Quain- 
tance,  Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  340;  T.  B.  Symons  and  E.  N.  Cory, 
Bulletin  149,  Md.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  STONE   FRUITS  655 

trees  is,  however,  poorly  developed,  insipid,  and  covered  with 
the  sooty  fungus  so  as  to  be  almost  unsaleable,  and  the  trees  are 
stunted  and  rendered  more  liable  to  the  attack  of  other  insects. 

Life  History. — There  is  but  one  generation  a  year.  In  the 
winter  they  are  mostly  nearly  grown  female  scales.  These  mature 
early  in  the  spring  and  deposit  their  eggs  in  a  mass  beneath  the 
body,  wdiich  forms  the  hard  scale  above  them.  In  Missouri  the 
eggs  hatch  about  June  10th,  and  continue  to  hatch  for  a  month. 
The  male  scales  are  much  smaller  than  the  females,  elongate^ 
slightly  convex,  and  greenish-white  in  color.  Late  in  July  the 
winged  males  appear  and  live  about  a  week.  The  young  female 
scales  continue  growth  during  the  summer  and  hibernate  when 
about  two-thirds  grown. 

Control. — Lime-sulfur  wash  is  entirely  ineffective  against  this 
species.  Kerosene  emulsion  of  20  or  25  per  cent,  applied  during 
the  dormant  season  will  destroy  the  hibernating  females,  according 
to  Sanders.  Spraying  with  kerosene  emulsion  15  per  cent,  or 
whale-oil  soap,  1  pound  to  4  or  5  gallons  of  water,  just  as  the  eggs 
are  hatching,  is  possibly  the  best  treatment.  As  the  eggs  hatch 
for  the  period  of  a  month,  a  second  application  may  prove 
advisable. 

The  Black  Peach-aphis  * 

The  black  peach-aphis  is  a  native  species  which  has  been  most 
injurious  in  the  Middle  Atlantic  States,  but  has  become  widely 
distributed  on  nursery  trees.  It  attacks  the  roots,  tender  shoots 
and  foliage  of  the  peach.  When  occurring  on  the  roots,  trees  are 
often  seriously  injured  before  its  presence  is  suspected.  Young 
trees  are  particularly  affected,  the  injured  trees  having  a  yellowish 
sickly  foliage.  Usually,  however,  the  presence  of  the  aphides 
on  the  young  shoots  and  leaves  will  be  an  indication  of  its  inhab- 
iting the  roots  also.  In  the  spring  and  early  summer  the  aphides 
cluster  on  the  tender  shoots  at  the  crotch  of  the  tree  and  low 

*  Aphis  persicoe-uigtr  Er.  Sm.  Family  Aphididoe.  See  C.  P.  Gillette, 
Bulletin  1,3.3,  Colo.  Agr.  Exp.  Sta.,  p.  37;  A.  L.  Quaintance,  Journal  of  Eco- 
nomic Entomology,  Vol.  I,  p.  308,  Yearbook  U.  S.  Dept.  Agr.,  1905,  p.  342. 


656      INSECT  PESTS  OF   FARM,   GARDEN   AND   ORCHARD 

down  on  the  limbs  and  soon  form  a  disgusting  black  mass  over 
the  3'oung  leaves,  which  ai'c  tightly  curled  up  from  the  injury. 
On  }'oung  trees  in  the  nursery  and  on  3'oung  orchard  trees,  this 
injury  to  the  foliage  is  sometim(\s  so  severe  as  to  kill  or  severely 
check  the  growth. 

Both  winged  and  wingless  aphides  are  fountl  on  the  foliage, 
]jut  only  the  wingless  forms  occur  on  the  roots.  Both  forms  are 
about  one-twelfth  inch  long  and  shining  deep  brown  or  black 
in  color  when  mature.  The  partly  grown  aphides,  which  form 
the  larger  part  of  most  colonies,  are  reddish-yellow  or  amber 
colored. 


Fig.  506. — The  black  peach-aphis  (Aphis  persicce-niger  Er.  Sm.):  winged 
viviparous  female;  young  female,  first  instar;  apterous  viviparous 
female — much  enlarged.     (After  Gillette  and  Taylor.) 


Life  History. — The  wingless  aphides  feetl  and  reproduce  upon 
the  roots  throughout  the  year,  all  l^eing  females  and  giving  birth 
to  live  young  after  the  manner  of  the  aphides.  In  the  spring 
some  of  them  migrate  to  the  young  foliage,  often  appeai'ing  on  the 
tender  twigs  before  the  buds  open.  They  multiph'  rapidly,  and 
as  a  result  of  the  hundreds  of  little  beaks  sucking  out  the  juices 
the  shoot  soon  withers,  which  causes  the  young  to  develop  into 
winged  aphides  which  migrate  to  other  trees.  Honey-dew  is 
excreted  very  freely  by  the  aphides,  which  are  therefore  attended 
by  numerous  ants  which  doubtless  aid  in  their  transportation 


INSECTS  INJURIOUS  TO  STONE  FRUITS  657 

from  tree  to  tree  and  from  the  roots  to  the  leaves  and  back. 
"  During  summer  the  aphides  for  the  most  part  are  to  be  found 
on  the  roots,  though  a  few  may  he  found  on  the  foliage  and  the 
shoots  in  badly  infested  orchards  at  almost  any  time  during  the 
growing  season.  Below  ground  they  occur  promiscuously  on 
roots  of  all  sizes,  but  the  smaller  and  more  tender  ones  are  pre- 
ferred. Some  of  the  aphides  ma}'  retain  their  hold  on  the  roots 
after  the  trees  are  dug,  and  the  insect  is  thus  frequently  distributed 
on  nursery  stock.  .  .  .  Light  sandy  soils  are  worst  infested, 
though  they  have  l)een  fo'uid  in  ainmdance  on  stiff  clay  soils." 
(Quaintance,  I.e.).  Neither  the  true  sexual  forms  nor  the 
eggs  of  this  species  have  ever  been  observed,  and  theie  is 
room  for  a  much  better  knowledge  of  its  life  history.  It  is 
stated  by  some  writers  that  the  aphides  migrate  to  the  roots 
in  the  fall. 

Control. — The  roots  of  young  trees  suspected  of  being  affected 
should  be  carefully  examined  and  if  aphides  are  found  the}'  should 
be  dipped  in  strong  tobacco  water.  Nurserymen  prevent  injury 
by  making  liberal  applications  of  tobacco  dust  in  the  trench  and 
along  the  rows.  Tobacco  dust  may  also  be  used  against  the 
aphides  on  the  roots  of  orchard  trees  by  removing  the  surface 
soil  and  applying  a  liljeral  dressing  of  the  dust,  which  will  be 
leached  down  on  to  the  roots  by  the  rains.  It  should  be  applied 
over  the  smaller  roots.  The  treatment  for  the  root  forms  has 
not  been  sufficiently  studied  to  warrant  any  conclusions  as  to 
satisfactory  methods,  but  the  same  as  advised  for  the  woolly  apple- 
aphis  (p.  587)  are  suggested.  When  the  aphides  appear  on  the 
young  shoots  in  the  spring  they  may  l^e  readily  controlled  if  the 
trees  are  observed  for  their  appearance,  for  they  ai'e  very  gregar- 
ious, clustering  on  one  shoot  until  it  is  well  covered  before  spread- 
ing to  the  rest  of  a  tree,  and  becoming  abundant  on  it  before 
spreading  to  others.  Often  the  small  infested  shoots  may  simply 
be  broken  off  and  destroyed.  The  aphides  may  be  killed  by 
spraying  them  wdth  kerosene  emulsion,  15  per  cent  kerosene, 
tobacco  extracts  or  whale-oil  soap,  1  pound  to  4  gallons.  The 
spray  should  be  applied  with  force  so  as  to  penetrate  the  honey- 


658         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

dew  and  curled  leaves,  and  should  be  applied  early,  as  after  the 
leaves  aremuch  curled  it  is  difficult  to  reach  the  aphides. 

The  Green  Peach-aphis  f 

This  aphid  is  a  European  species  which  has  long  ])een  known 
as  a  pest  of  peach  foliage  in  this  country,  where  it  has  become 
widely  distributed.  Considerable  interest  attaches  to  the  species, 
as  it  furnishes  a  striking  example  of  the  summer  migration  of 
aphides  to  different  food-plants,  and  a  consequent  difference 
in  appearance  in  form  and  color.  During  the  summer  this  species 
feeds  upon  various  vegetables  and  succulent  plants,  and  is  so 
different  in  color  and  form  that  it  has  been  well  known  not  only 
as  a  separate  species,  but  as  belonging  to  a  distinct  genus.  Con- 
cerning its  injury  to  the  peach,  E.  P.  Taylor  states:  "The 
peach-growers  of  Western  Colorado  have  suffered  loss  from  it, 
from  its  heavy  infestation  of  the  leaves  of  the  trees  in  the  spring, 
causing  them  to  curl  and  drop  prematurely  to  the  ground,  and 
from  the  withering  and  subsequent  dropping  of  the  buds  and 
forming  peaches  also  infested  by  the  aphides  at  this  time." 
Similar  injury  has  been  reported  from  Missouri,  and  doubtless 
occurs  occasionally  in  other  sections. 

Life  History. — The  winter  is  usually  passed  in  the  egg  stage 
on  the  peach,  plum,  apricot,  nectarine,  cherry  or  other  trees, 
though  the  wingless  females  sometimes  persist  on  the  summer 
food-plants  where  there  is  sufficient  protection  to  enable  them  to 
endure  the  cold  of  winter,  as  in  cabbage  pits,  or  in  the  South. 
The  small,  oval,  shining  black  eggs  are  deposited  in  the  axils  of 
the  buds  or  in  crevices  of  the  bark.  '!  The  eggs  hatch  very 
early  in  the  spring  so  that  the  young  stem-mothers  from  them 
are  often  almost  fully  grown  before  the  earliest  peach  or  plum 
blossoms  open.  About  the  time  the  buds  begin  to  open  on  these 
trees,  the  stem-mothers  are  all  of  a  deep  pink  color  and  begin  to 

*  Myzus  persicoe  Sulz.  Family  Aphididoe.  (Syn. — Rhopalosiphum  diantJii 
Schr.)  See  Gillette  and  Taylor,  Bulletin  133,  Colo.  Agr.  Exp.  Sta.,  p.  32; 
C.  P.  Gillette,  Journal  of  Economic  Entomology,  Vol.  I,  p.  359;  E.  P.  Taylor, 
ihid.,  p.  83;   F.  H.  Chittenden,  Bulletin  2,  Va.  Truck  Exp.  Sta.,  p.  30. 


INSECTS  INJURIOUS  TO   STONE  FRUITS 


659 


give  birth  to  living  young.  These  young  instead  of  being  pink 
hke  their  mothers  nvo  pule  yellowish-gi-een  throughout  their 
lives,  and  usually  there  is  a  median  and  two  lateral  dark  green 
stripes  passing  over  the  abdomen.     Very  few  of  this  brood  attain 


Fig.  507. — The  green  peach  Aphis  {Myzus  persicce  Sulz.):  5,  adult  stem 
mother;  6,  young  of  stem  mother;  7,  apterous  viviparous  female  of 
second  generation;  8,  spring  migi-ant;  9,  fall  migrant;  10,  egg-laying 
female;    11,  eggs — all  much  enlarged.     (After  Gillette  and  Taylor.) 

wings.  The  third  generation  become  very  largely  winged  and 
begin  leaving  the  trees  upon  which  they  were  born  about  the  mid- 
dle of  May  in  the  peach-growing  sections  of  the  State  (Colorado) . 
By  the  middle  of  June  these  lice  have  almost  completely  left  the 


660       INSECT  PESTS  OF   FARM,   GARDEN  AND  ORCHARD 

trees  and  may  be  found  establishing  their  colonies  upon  various 
succulent  vegetables/'  such  as  cabbage,  turnip,  rape,  tomato, 
celery,  and  a  long  list  of  vegetables  and  flowers  grown  in  green- 
houses, where  this  species  is  a  pest  the  year  round.  The  list  of  food- 
plants  is  a  long  one,  the  largest  of  any  species  known  to  him,  accord- 
ing to  Professor  C.  P.  Gillette,  but  it  is  a  common  and  sometimes 
troublesome  pest  of  cabbage  (See  p.  374)  and  celery  and  one  of 
the  most  abundant  of  the  various  sorts  of  "  green  fly  "  of  the 
greenhouse.  The  winged  females  which  migrate  from  the  peach 
are  about  one-twelfth  inch  long,  with  a  wing  expanse  of  one-third 
inch.  They  are  a  yellowish-green  color  with  head,  antennae, 
thoracic  lobes,  honey-tubes,  a  large  spot  on  the  centre  of  the 
abdomen,  and  small  lateral  spots  in  front  of  the  honey-tubes  are 
blackish.  The  honey-tubes,  or  cornicles,  are  cylindrical,  while 
those  of  the  winged  females  in  summer  and  fall  are  decidedly 
swollen  toward  the  tip  and  constricted  at  the  base,  giving  them 
a  club  shape,  on  account  of  which  they  were  placed  in  the  genus 
Rhopalosiphum.  Otherwise  the  winged  females  of  summer  and 
fall  are  very  similar,  except  that  they  are  more  yellowish  and  the 
markings  and  cornicles  are  lighter.  The  wingless  females  during 
the  summer  are  pale  yellowish  and  lack  the  longitudinal  green 
stripes  on  the  abdomen.  According  to  Taylor's  observations  the 
spring  generations  on  peach  become  full  grown  in  about  two 
weeks  and  an  individual  aphid  lives  about  a  month.  As  repro- 
duction, is  probal)ly  more  rapid  in  summer,  the  aphides  may  soon 
become,  very  aljundant.  In  the  fall  wunged  females  return  to  the 
peach  and  winter  host-plants,  and  give  birth  to  young  which 
develop  into  wingless  females  which  lay  the  winter  eggs.  The 
true  males  are  winged  and  migrate  from  the  summer  food-plants. 
Control. — The  trees  affected  should  be  sprayed  about  a  week 
before  the  buds  open  with  5  to  7  per  cent  kerosene  emulsion, 
tobacco  extract,  or  whale-oil  soap,  1  pound  to  5  gallons,  or  miscible 
oil  diluted  20  times.  If  the  trees  are  sprayed  with  lime-sulfur # 
for  the  twig-borer  just  before  blossoming,  it  should  kill  most  of 
the  aphides.  The  same  remedies  may  be  used  on  the  foliage  of 
affected  plants  as  necessary. 


INSECTS  INJURIOUS   TO   STONE   FRUITS 


601 


The  Plum  Gouger  * 

This  is  a  native  species  which  breeds  upon  wild  plums  and  is 
most  injurious  to  native  varieties.  It  is  common  throughout 
the  Mississippi  Valley,  but  seems  to  be  most  injurious  westward 
and  occurs  in  ColoradD.  The  work  of  the  beetles  might  be  easily 
mistaken  for  that  of  the  curculio  (p.  576).  The  adult  beetle  is 
readily  distinguished  from  the 
curculio,  ]iow(>ver.  Iiy  lacking 
the  humps  on  the  wiiig-covers. 
It  is  about  on(>-(|uart{n'  inch 
long,  with  a  snout  half  as  long, 
the  wing-covers  are  a  leaden- 
gray  color,  finely  spotted  with 
black  and  brown,  while  the 
thorax  and  head  are  marked 
with  ochreous  yellow. 

Life  History.  Like  the  cur- 
culio the  beetles  hibernate  over 
winter  and  appear  in  the  spring 
as  the  trees  blossom.  At  first 
the}'  puncture  the  calyx  and  feed 
on  the  ovary  of  the  flower,  com- 
pletely destroying  it  for  fruit  pro- 
duction, and  then  puncture  the 
growing  plums,  both  for  food 
and  for  egg-laying.     In    feeding 

on  the  plums  the  adults  gouge  out  small  round  holes,  from  which 
gum  exudes.  Like  the  curculios,  they  have  the  habit  of  feigning 
death  and  dropping  to  the  ground  when  disturbed.  The  eggs 
are  laid  while  the  pit  of  the  plum  is  still  soft.  The  female  beetle 
drills  a  small  hole  in  the  plum,  which  is  larger  below,  and  in  it 
deposits  a  small  yellowish-white  egg,  whose  outer  end  lies  flush 
with  the  surface  of  the  plum.  As  soon  as  the  larva  hatches  it 
eats  its  way  into  the  pit,  feeding  upon  the  meat  of  the  seed  until 


Fig.  508. — The  plum  gouger  {Cocco- 
torus  scidellaris  Lee):  a,  plum 
stone  showing  exit  hole  of  larva; 
b,  adult ;  c,  side  view  of  head  of 
beetle — enlarged.  (After  Riley 
and  Howard,  U.  S.  Dept.  Agr.) 


*  Coccotorus  scutellaris  Lee,.     Family  Curciilionidce, 


662      INSECT  PESTS   OF   FARM,    GARDEN  AND  ORCHARD 

full  grown.  It  then  cats  a  hole  through  the  outside  of  the  pit  so 
that  the  adult  beetle  may  escape,  and  then  transforms  to  a  pupa. 
The  larva  is  very  similar  to  that  of  the  ourculio,  but  is  a  milky 
white  rather  than  a  glossy  white  and  lacks  the  reddish  tinge  on 
the  lower  surface.  Affected  plums  do  not  drop  as  when  injured 
by  the  curculio.  The  pupal  stage  is  passed  in  the  pit  of  the  plum 
and  the  adult  beetle  emerges  through  the  hole  cut  for  it  by  the 
larva.  The  beetles  emerge  a  little  before  the  plums  ripen  and 
often  practicall}'  destroy  them,  as  fruit  badly  punctured  becomes 
gnarly  and  worthless.  The  beetles  feed  on  th(>  plums  a  short  time 
and  then  seek  hibernating  quarters  for  the  winter. 

Control. — Jarring  the  trees  as  for  the  curculio  is  the  only 
method  of  control  which  has  been  successfully  used,  but  where 
the  beetles  are  abundant  it  would  be  well  to  try  spraying  with 
arsenate  of  lead  as  advised  for  the  curculio  (p.  580). 

Plum  Aphides 

Three  species  of  aphides  are  common  on  the  p'um  foliage  in 
spring  and  fall,  and  often  do  serious  damage  by  curling  up  the 
foliage  in  the  spring  and  causing  it  to  drop  prematurely,  thus 
checking  the  growth  of  the  tree  and  preventing  proper  fruiting. 
The  life  histories  of  the  three  species  are  very  similar  in  that  the 
eggs  are  laid  upon  the  plum  in  the  fall,  upon  which  two  or  three 
generations  develop  in  the  spring,  but  in  early  summer  they 
migrate  to  other  food-plants,  from  which  they  return  to  the  plum 
in  the  fall.  The  life  history  is  much  the  same  as  that  of  the 
apple-aphis  (p.  658),  and  green  peach-aphis  (p.  597),  and  need  nob 
be  rehearsed  in  detail. 

The  Mealy  Plum-louse  * 

This  is  a  light-green  species  w^hich  is  covered  by  a  Ijluish-white 

mealy  powder.     It  has  a  long  narrow  body,  one-tenth  inch  long, 

*  Hyalopterus  arundinis  Fab.  Family  Aphididce.  W.  D.  Hunter  in 
Bulletin  60,  Iowa  Agr.  Exp.  Sta.,  p.  92,  states  that  Aphis  prunifolice  Fitch 
is  probably  the  same  species.  Certahily  H.  arundinis  and  pruni,  Aphis 
pruni  and  prunifolice,  seem  to  have  been  applied  to  the  same  species  in  the 
economic  literature  in  America.  See  Lowe,  V.  L.,  Bulletin  139,  N.  Y.  Agr 
Exp.  Sta.,  p.  657. 


INSECTS  INJURIOUS  TO  STONE  FRUITS 


663 


marked  with  three  lon^itiulinal  stripes  of  a  darker  green.     The 
honey-tubes  are  short,  thick,  antl  slightly  constricted  at  the  base. 


Fig.  509. — The  mealy  plum  louse  (Hyalopterus  arundinis  Fab.):  a,  young 
njTnph;  b,  last  stage  of  nymph  of  winged  form;  c,  winged  viviparous 
female — all  much  enlarged.     (After  Lowe.) 

The  winged  female  is  similar  in  coloration  except  that  the  abdomen 
bears  several  transverse  triangular  marks  of  darker  green.     In 


Fig.  510. — Mealy  plum  aphides  clustered  on  leaf.     (After  Lowe.) 

June  the  winged  females  migrate  to  certain  grasses  upon  which 
the  aphides  reproduce  during  the  summer,  though  small  colonies 
are  to  be  found  on  the  plum  throughout  the  summer.     In  the 


664       INSECT  PESTS   OF  FARM,  GARDEN  AND  ORCHARD 

fall  they  return  to  tlic  plum,  where  the  winter  e^'gs  are  laid.  ThivS 
species  is  known  to  occur  in  Germany,  England,  Australia,  and 
New  Zealand,  and  seems  to  be  widely  distributed  over  the  United 
States.  It  occurs  here  on  plum  and  prune  and  in  Europe  is  said 
to  infest  grape,  peach,  apricot,  and  nectarine,  according  to  Lowe. 

The  Hop  Plant-louse  * 

This  species  is  best  known  as  a  pest  of  hops  (see  p.  275)  during 
the  summer  and  rarely  does  very  serious  damage  to  the  plum, 
though  often  quite  abundant  on  it.  The  wingless  aphides  are 
light  green  or  yellowish  green  without  any  noticeable  markings. 
The  winged  forms  have  the  same  body  color,  with  the  head,  thoracic 
lobes,  and  a  few  dashes  on  the  abdomen  black.  The  species 
may  be  readily  distinguished  by  the  prominent  tubercle  which 
projects  from  the  head  on  the  inside  of  the  base  of  each  antenna, 
and  a  less  prominent  tubercle  on  the  basal  segment  of  each 
antenna,  as  shown  in  Fig.  204.  According  to  the  studies  of  Dr. 
C.  V.  Riley  and  his  assistants,  the  third  generation  in  the  spring 
migrates  from  the  plum  to  hops  in  late  spring  and  in  fall  winged 
viviparous  females  give  birth  to  a  few  young  which  develop  into 
egg-laying  females  which  mate  with  winged  males  which  have  devel- 
oped on  hops,  the  winter  eggs  being  laid  on  the  plum  and  other 
species  of  Prunus.  In  California  Clarke  has  been  unable  to  find 
any  evidence  of  the  species  on  plum  or  other  vegetation  outside 
of  the  hop  yards,  where  he  finds  the  true  sexes  occuri'ing  in  (he 
fall,  l)ut  no  evidence  of  eggs.  Hops  are  often  seriously  damaged 
])y  Ijeing  reduced  in  size  antl  weight  and  from  the  loss  in  aroma 
due  to  the  presence  of  the  aphides  in  them.  The  species  is  of 
European  origin,  where  it  is  a  well-known  enemy  of  hops,  and  has 
become  widely  distributed  in  the  United  States  and  Canada. 

Control. — Where  it  ovipos'.ts  on  plum  it  may  be  best  con- 
trolled by  spraying  as  for  the  other  plum  aphides  in  the  spring. 
After  it  becomes  established  on  hops  it  may  be  controlled  by 

*  Phorodon  humuli  Schrank.  Family  Aphididoe.  See  page  275  above. 
See  C.  V.  Riley,  Report  U.  S.  Dept.  Agr.,  1888,  p.  93;  W.  T.  Clarke,  Bulletin 
ICO,  Cal.  Agr.  Exp.  Sta. 


INSECTS  INJURIOUS  TO  STONE  FRUITS  665 

spraying  with  whale-oil  soap,  1  pound  to  6  gallons  of  water,  or 
by  the  addition  of  quassia  chips,  which  has  long  been  the  favorite 
remedy  of  hop-growers,  6  to  8  pounds  of  quassia  chips  are 
steeped  in  cold  water  for  a  day  or  two  and  then  boiled  for  an 
hour,  when  they  are  mixed  with  4  or  5  pounds  of  soft  soap,  whale- 
oil  soap  being  excellent,  and  100  gallons  of  water. 

The  Rusty-brown  Plum-louse  * 

This  species  is  readily  distinguished  from  others  common  on 
plum  and  prune  by  the  dark  rusty-brown  color,  with  the  base 
of  the  antenna),  tibia),  and  tail  a  contrasting  white.  This  species 
has  become  a  very  serious  pest  to  plum  foliage  in  the  South  and 
Southwest,  and  we  have  observed  serious  injury  in  New  Hamp- 
shire, so  that  it  is  evidently  widely  distributed.  The  aphides 
collect  on  the  tender  young  twigs,  which  they  stunt  or  kill,  assemble 
on  the  under  sides  of  the  leaves,  which  become  corrugated  and 
curled  from  their  attack,  and  when  abundant  they  attack  the 
blossoms  and  their  stems  and  thus  prevent  the  setting  of  fmit. 
In  early  summer  the  winged  females  migrate  to  various  common 
grasses,  such  as  fox-tail,  red  top,  barnyard  grass,  crab  grass,  and 
others,  upon  which  they  breed  during  the  summer,  and  from  which 
the  winged  forms  return  to  plum  in  the  fall.  They  become 
darker  in  color  late  in  the  season  and  the  wingless,  egg-laying 
female  is  almost  black,  as  is  also  the  small  winged  male. 

Control. — The  treatment  advised  for  the  apple-aphis  (p.  658) 
will  be  effective  for  the  three  species  above  while  on  the  plum, 
and  for  that  and  other  species,  the  spraying  should  be  done 
early  in  the  season  before  the  aphides  have  become  numerous 
and  curled  the  foliage. 

*  Aphis  setarice  Thos.  Family  Aphididce.  See  Gillette  and  Taylor, 
Bulletin  133,  Colo.  Agr.  Exp.  Sta.,  p.  41;  C.  E.  Sanborn,  Bulletin  88,  Okla- 
homa Agr.  Exp.  Sta. 


666      INSECT  PESTS  OF   FARM,    GARDEN  AND   ORCHARD 

The  Black  Cherry-louse  * 

This  species  has  long  been  known  as  a  cherry  pest  in  Europe 
and  during  the  last  fifty  years  has  become  generally  distributed 
over  the  eastern  United  States,  and  occurs  in  Colorado.  So  far 
as  known  the  cherry  is  the  only  food-plant.  Dr.  Weed  was  of 
the  opinion  that  the  aphides  left  the  cherry  during  late  July 
and  migrated  to  some  summer  food-plant  which  he  was  unable  to 


•■f^^^r^mnmsisz  ^.'^^ua^ 


Fig.  511. — The  black  cherry-aphis  {Myzus  cerasi  Fab.):  1,  apterous  vivip- 
arous female;  2,  winged  viviparous  female — enlarged.  (After  Gillette 
and  Taylor.) 

find,  but  observations  by  Gillette  and  Taylor  in  Colorado  would 
indicate  that  they  may  remain  on  the  cherry,  but  become  so 
reduced  in  numbers  by  their  natural  enemies  that  onl}'  a  few 
survive  during  midsummer,  and  these  give  rise  to  larger  colonies 
in  late  summer  and  early  fall.  Both  the  winged  and  wingless 
forms  are  deep  shining  black,  the  body  is  rather  Inroad  and  flat, 
and  the  honey-tubes  are  unusually  long  and  are  cylindrical. 
Small  winged  males  and  wingless  females  occur  on  the  foliage  in 
the  fall  and  the  latter  lay  their  eggs  on  the  twigs  about  the  buds. 
Like  the  black  peach-aphis,  this  species  has  the  habit  of  accumula- 
ting in  large  numbers  on  the  smaller  sprouts  or  liml)s  near  the 

*  Myzus  cerasi  Fab.  Family  Aphididce.  See  C.  M.  AVeed,  Bulletin  Ohio 
Agr.  Exp.  Sta.,  Tech.  Ser.,  Vol.  I,  No.  2,  p.  Ill;  C.  P.  Gillette,  Journal  of 
Economic  Entomology,  Vol.  I,  p.  362. 


INSECTS  INJURIOUS  TO  STONE  FRUITS 


667 


ground  before  spreading  to  the  rest  of  the  tree  or  other  trees,  so 
that  prompt  treatment  when  first  observed  will  prevent  general 
infestation. 

Control. — Spraying  with  kerosene  emulsion,  whale-oil  soap, 
tobacco  extracts,  or  dilute  miscible  oils,  as  for  the  apple-aphis 
(p.  658),  will  control  the  pest. 

The  Cherry  Fruit-fly  f 

The  cherry  fruit-fly  is  a  native  insect  whose  maggot  lives  in 
the  flesh  of  the  cherries,  causing  them  to  rot.  It  is  very  nearly 
related  to  the  apple  maggot  (p.  632)  which  it  very  closely  resembles 


Fig.  512. — The  cherry  fruit-fly  {Rhagoletis  cingulata  Loew.) :  a,  fly;  h,  maggot; 
c,  anterior  spiracles  of  same;  (/,  puparium;  e,  posterior  spiracular  plates 
of  pupa — all  enlarged.     (After  Chittenden,  U.  S.  Dept.  Agr.) 

in  both  appearance  and  life  history.  Injury  by  it  has  been 
recorded  in  Massachusetts,  New  York,  Ontario,  Pennsylvania, 
District  of  Columbia,  Michigan  and  Iowa,  so  that  it  is  probably 
generally  distributed  over  the  northeastern  States.  Although 
its  native  food-plant  is  unknown  it  is  probable  that  it  lives  on  some 
wild  sour  cherry.     As  cherries  are  always  more  or  less  injured 

t  Rhagoletis  cingulata  Loew.  Family  Trypetidoe.  See  M.  V.  Slingerland 
Bulletin  172,  Cornell  Univ.  Agr.  Exp.  Sta.;  F.  H.  Chittenden,  Bulletin  44^ 
Bureau  of  Entomology,  U.  S.  Dept.  Agr.,  p.  70. 


668         INSECT  PESTS  OF  FARM,  GARDEN  AND  ORCHARD 

by  the  plum  curculio  (p.  576),  it  is  quite  probable  that  injury 
by  this  maggot  may  have  been  attributed  to  the  curculio  and  its 
identity  passed  unnoticed.  Sour  and  sul^acid  varieties,  such  as  the 
Morello  and  Montmorency,  are  worst  injured,  but  black  cherries 
and  indeed  all  varieties  are  more  or  less  damaged. 

The  fly  is  slightly  smaller  than  that  of  the  apple-maggot,  being 
about  one-sixth  inch  long  with  a  wing  expanse  of  three-eighths 
inch.  The  body  is  blackish,  the  head  and  legs  are  pale  yellowish- 
brown,  the  sides  of  the  thorax  are  marked  with  a  longitudinal 


Fig.  513. — Section  of  a  cherry,  enlarged  to  show  the  maggot  of  the  cherry 
fruit-fly  and  nature  of  its  work.  The  small  figures  above  show  the 
maggot  and  parent  fly  natural  size.     (After  SUngerhind.) 

yellow  band,  the  abdominal  segments  are  marked  with  whitish 
or  pale  brownish  transverse  bands,  and  the  wings  are  crossed  by 
four  Ijlackish  bands.  The  maggot  is  about  one-quarter  inch 
long  and  is  indistinguishable  from  the  apple-maggot. 

Life  History. — The  eggs  are  deposited  just  under  the  skin 
of  the  cherry  from  June  until  .\ugust.  or  probably  during  the 
whole  season  of  the  fruit.  The  eggs  hatch  in  a  few  days  and  the 
little  maggots  penetrate  to  the  pits,  feeding  on  the  flesh  and 
forming  a  rotting  cavity  very  similar  to  that  made  by  the  grub  of 
the  curctdio.    But  few  of  the  affected  cherries  fall  from  the  trees, 


INSECT8  INJURIOUS  TO   STONE  FRUITS  669 

uiul  ius  llicy  ri('(iuciil  ly  show  I  ml  little  cITccI  of  the  (hiiiiagc,  (Ik; 
infcvsted  fruit  may  he  luaikdcd  and  the  pest  thus  spi'(>a<l.  When 
full  grown  the  maggots  leave  the  cherries  and  form  {)uparia  just 
beneath  the  surface  of  the  ground,  or  in  the  bottom  of  ])askets 
or  in  rul)bish,  wherevcn*  the  affected  fruit  may  be.  The  flies 
conuiience  to  emerge  from  these  puparia  by  the  middle  of  June 
in  New  York  and  are  found  during  the  summer  months. 

Control. — There  is  but  little  evidence  as  to  practical  means  of 
control.  Deep  plowing  in  spring  should  result  in  burying  the 
puparia  so  deeply  as  to  prevent  the  emergence  of  the  flies.  Cultiva- 
tion is  evidently  of  little  value,  as  the  pest  occurs  in  well-cultivated 
orchards,  so  that  shallow  cultivation  does  not  seem  to  affect  the 
puparia.  Chickens  have  been  observ(>d  to  destroy  the  puparia, 
and  will  doubtless  prove  as  effective  as  against  the  apple-maggot 
where  they  can  be  confined  beneath  affected  trees  on  cultivated 
soil.  The  destruction  of  all  fruit,  whether  windfall  or  remaining 
on  the  tree  will,  of  course,  aid  in  control.  Recently  a  nearly 
related  fruit-fly  has  been  successfully  controlled  in  South  Africa 
by  spraying  the  foliage  with  arsenate  of  lead  sweetened  with 
treacle  or  brown  sugar,  thus  attracting  the  flies,  which  are  poisoned 
by  the  arsenate,  and  this  method  is  worthy  of  trial  both  for  the 
cherry  fruit-fly  and  apple-maggot. 


INDEX 


Abbot's  sphinx,  530 
Acarina,  G36 

Achemon  sphinx,  520,  527 
Acriihdae,  93 
Adalia  bii)unclata,  10 
Adoxus  vitis,  504 
iEgeria  tipuHformis,  477 
Agrilus  ruficollis,  466 
Agriotes  mancus,  82,  83 
Agromyza  simplex,  428 
Agromyzidae,  428 
Agrotis  annexa,  88 

messoria,  85 

ypsilon,  85 
Air-tubes,  29 
Alabama  argillacea,  243 
Alfalfa  weevil,  205 
Alimentary  canal,  30 
Alkah  bug,  337 
AJsophila  pometaria,  572,  573 
Alwood,  W.  B.,  584 
American  frit-fly,  134,  135 
Amphicerus  bicaudatus,  513 

punctipennis,  515 
Ampeloglypter  ater,  511 

sesostris,  509 
Ampelophaga  myron,  528 
Anarsia  lineatella,  650 
Anasa  tristis,  388 
Anatomy,  internal,  30 
Ancyhs  comptana,  452 
Angoumois  grain-moth,  192 
Ant,  corn-field,  165,  168 
Antennae,  22 

Anthomyia  egg  parasite,  106 
Anthomyiida;,    320,    345,    347,    420, 
423,  469 


Anthonomus  grandis,  261 

quadrigibbus,  634 
signatus,  456 
Anf  s  and  plant-lice,  165,  444 
Apanteles  congregatus,  234 
Aphides,  plum,  662 
Aphidida;,   147,   150,   164,  211,  241, 
275,  317,  330,  383,  441,  484,  492, 
582,  597,  602,  604,  606,  655,  658, 
662,  664,  665,  666 
Aphidius  avenaphis,  19,  149 

spp.,  325 
Aphis,  apple,  597 

bakeri,  606,  607 

bean,  317 

brassicse,  371 

burr-clover,  241 

cabbage,  371 

clover,  606 

corn  root-,  164 

currant,  484 

Enghsh  grain,  147 

fitchii,  604 

forbesi,  441 

German  grain,  148 

gossypii,  241,  383 

grass  root-,  167 

hop,  275 

maidi-radicis,  164 

maidis,  170 

medicaginis,  241 

melon,  241,  383 

pea,  322 

persicse-niger,  655 

pomi,  597,  607 

prunifolia;,  662 

pyri,  602 

671 


672 


INDEX 


Aj)his,  ruinicis,  317 
setaria>,  665 
sorbi,  G02 
spinach  or  green-i)each,  375, 

658 
spring  grain,  150 
Apparatus,  dusting,  77 

spraying,  60 
Apple  aphis,  579 

woolly,  582 
rosy,  602 
curculio,  634 
insects,  5S2 
leaf-minor,  61(5 
maggot,  632 
j)lant-hce,  597 
tree-borer,  flat-headed,  591 

round-headed,  588 
worm,  624 

lesser,  628 
Arachnida,  636 
Arctiida^,  247,  553 
Argus  tortoise-beetle,  436 
Army  worm,  3,  114 

beet,  334 
faU,  118 
Arsenate  of  lead,  43 
Arsenicals,  harmlessness  of,  47 
Arsenite  of  lead,  44 
Arsenite  of  Ume,  45 
Asaphes  decoloratus,  83 
Asparagus  beetle,  424 

twelve-sj)otted,  427 
miner,  428 
Aspidiotus  perniciosus,  538 
Atomizers,  60 
Aulaciz(>s  irrorata,  250 
Autographa  brassica.',   361 

Ball,  I'].  D.,  339 
Baltimore  oriole,  307 
Banded  flea-beetle,  402 
Bark-beetle,  fruit-tree,  544,  653 

peach-tree,  653 
Barred-winged  onion  maggot,  423 
Bean-aphis,  317 
Bean  insects,  305 


Bean  ladybird,  315 

leaf -beetle,  313 

-weevil,  309 

European,  313 
four-spotted,  312 
Bee-flies,  106 
Beet-aphis,  330 

armyworm,  334 

leaf-beetle,  larger,  337 

loaf-hopper,  339 

loaf-minor,  345 

root-aphis,  331 
Uoiiil)(«'ia  marginata,  459 
BiU-bugs,  175 

maize,  178 
Bishoi^p,  F.  C,  254 
Blackberry  gallmaker,  468 
Blackbird,  crow,  307 
Black  cherry-louse,  666 
Black-legged  tortoise-beetle,  434 
Black  peach-aphis,  655 
Black   swallow-tail  butterfly,   411 
Blissus  leucopterus,  89 
Blister-beetle,  ash-gray,  316 
Nuttall's,  317 
striped,  343 
Blister-beetles,    107,    301,    315,    343 
Blister-mite,  pear-leaf,  636. 
Blood,  of  insects,  30 
Boll  weevil,  cotton,  261 
Bollworm,  cotton,  181,  254 
Bordeaux  mixture,  56 
Borer,  cotton-square,  248 
hop-plant,  273 
peach,  645 
Brachymena  4-pustulata,  25 
Braconid*,  18,  149,  374,  385,  557 
Bracon  mellitor,  270 
Bran-mash,  poisoneti,  47 
Breathing,  of  insects,  28 
Britton,  W.  E.,  570,  572,  573,  602, 

621,  623 
Brooks,  F.  E.,  497,  509,  511,  534,  537, 

634 
Brown-tail  moth,  5,  558 
Bruchida?,  305,  309 
Bruchophagus  funebris,  214 


INDEX 


673 


Bruchus  chinoiisis,  311 

obtoctus,  ;3()9 

j)isoruiii,  305 

(luadriinaculatus,  312 

rufimamis,  313 
liriK's,  C.  T.,  241,  254 
liruner,  L.,  449 
Hryobia  pratensi.s,  209 
Buhach,  55 
Bud-moth,  621 
Bud-worm,  159,  161,  172,  234 

tobacco,  181 
Buffalo  tree-hojiper,  547 
Bupre.stida\  466,  591 
Burr-clover  aphis,  241 
Burning,  for  insects,  38 
Byturus  unicolor,  474 

Cabbage-aphis,  371 

-bug,  harlequin,  368 

butterfly, southern,  360 

curculio,  377 

flea-beetle,  western,  375 

insects,  37 

looper,  361 

maggot,  34,  347 

plutella,  366 

webworm,  imjiorted,  365 
-worm,  cross-striped,  363 
-worm,  imported,  355 
C'adelle,  188 
(^'alandra  granaria,  ISO 

oryza>,  186 
Calandridse,  175,  186 
Calosoma  calidum,  15 

•  scrutator,  16 
Calico-back,  368 
California  peach-tree  borer,  645 
Calocoris  rapidus,  251 
Camnula  pellucida,  99 
Cane-borer,  grape,  513 

raspberry,  462 
red-necked,  466 
Canker-worm,  fall,  572 

spring,  570 
Cantharis  nuttalli,  317 
Capsidaj,  226,  251,  404,  481 


Carabida",  14 

Carbon  bisulfid,  57 

Carrot  beetle,  414 
rust-fly,  415 

Case-bearer,  cigar,  ()1S 
l)islol,  ()18 

C'assida  bivittata,  433 
nigripes,  434 

Cassida;,  432 

Caterpillar,  apple,  red-humped,  615 
yellow-necked,  613 
celery,  411 
clover-seed,  216 
hog,  grai:)e-vine,  528 
salt-marsh,  247 
tent,  608 

white-lined  sphinx,  247 
woolly-bear,  247 

Cathartus  ad  vena,  188 

gemellatus,  188 

Cattle,  tick,  6 

Cecidomyida^,  123,  145,  212 

Celery  caterpillar,  411 
leaf-tyer,  409 
looper,  413 

Cephidse,  129 

Cephus  occidentalis,  130 
pygmseus,  129 

Cerambycidic,  462,  588 

Cereals,  insect  injury  to,  2 

Ceratoma  trifurcata,  313 

Ceresa  bubalus,  547 

Ceutorhinchus  rapa',  377 

Chalcid,  clover-seed,  214 

Chalcididaj,  136,  138,  214 

Chalcis  flies,  19,  545 

Chajtocnema  confinis,  430 

Chatopsis  a^nea,  423 

Chelymorpha  argus,  436 

Cherry  fruit-fly,  667 

Chinch-bug,  2,  37,  89 
false,  339 

Chionaspis  furfura,  595,  596 

Chiropachis  colon,  545 

Chitin,  23 

Chittenden,  F.  H.,  129,  178,  186,  197 
258,  261,  291,  305,  307,  320,  322, 


674 


INDEX 


Chittenden,  F.  H. — Conlinued 

330,  335,  338,  345,  347,  355,  361, 
363,  365,  368,  378,  379,  383,  388, 
391,  402,  408,  413,  415,  418,  424, 
428,  456,  478,  544,  588,  658,  667 
Chloridea  virescens,  234 
Chrysalis,  24 

Chrysobothris  femorata,  591 
ChrysomeHda,    157,    158,   222,    291, 
303,  313,  335,  337,  375,  379,  402, 
424,  427,  430,  448,  501,  515 
Chrysopidse,  325,  385 
Cicada,  mouth-parts,  28 
periodical,  548 
septendecim,  548 
Cicadidae,  548 
Cigar  case-bearer,  618 
Cigarette  beetle,  239 
Clarke,  W.  T.,  289,  650,  664 
Clover-aphis,  606 

-hay  worm,  219 
insects,  200 
leaf-weevil,  203 
mite,  209 
root-borer,  200 
-seed  chalcid,  214 
midge,  212 
caterpillar,  216 
stem-borer,  202 
Coccidffi,  538,  592,  595,  654 
Coccinella  novemnotata,  9,  385 
Coccinellida;,  9,  315,  325,  385,  391 
Cocoon,  24 

Coccotorus  scutellaris,  661 
Codhng  moth,  4,  624 
CoeUnus  meromyzse,  135 
Colaspis  brunnea,  448 
Coleophora  fletcherella,  618 
malivorella,  618 
Colorado  potato-beetle,  291 
Comma  butterfly,  283 
Compressed-air  sprayers,  62 
Comstock,  J.  H.,  129,  438,  462,  464, 

539 
Conotrachelus  nenuphar,  576 
Conradi,  A.  F.,  165,  388,  440 
Cook,  A.  J.,  133 


Cooloy,  R.  A.,  596 
Coptocycla  bicolor,  435 

signifera,  436 
Coquillet,  D.  W.,  113,  570,  572 
Coreida",  252,  388 
Corn  ear-worm,  2,  181,  235 
-field,  ant,  168 
insect  injury  to,  2 
insects,  157 
leaf -aphis,  170 
-root  aphis,  164,  170 
web  worm,  161 
root-worm,  southern,  158 
western,  157 
stalk-borer,  37 

larger,  172,  181 
Cory,  E.  N.,  654 
Cotton-boU  cutworm,  258 

boU  weevil,  3,  34,  37,  261 
bollworm,  3,  40,  181,  254 
insect  injury  to,  3 
insects,  241 
leaf-bug,  251 
-hoppers,  250 
-worm,  4,  243 
square-borer,  248 
stainer,  253 
worm,  243 
Cowpea  weevil,  311 
Crambida^,  161,  172,  224 
Crambus  caliginosellus,  161,  224 
Crandall,  C.  S.,  576,  634 
Crane-flies,  121 
Craponius  ina?qualis,  534 
Crested  flycatcher,  501 
Criddle  mixture,  113 
Crioceris  asparagi,  424 

duodecimpunctata,  427 
Cross-striped  cabbage-worm,  363 
Crown-borer,  strawberry,  447 
Cucujidae,  187 

Cucumber  beetle,  striped,  159,  379 
Culture,  35 
Curculio,  apple,  634 

cabbage,  377 
grape,  534 
plum,  576 


INDEX 


675 


Ciirculio,  rhuliarl),  40S 
CurculionicUr,  203,  205,  2G1,  28"),  377, 
438,  447,  45G,  509,  511,  534,  57B, 
634,  661 
Currant-aphis,  484 

borer,  imported,. 477 
-fly,  490 
span-worm,  488 
stem-girdler,  478 
worm,  imported,  486 
native,  487 
Cutworm,  bronzed,  86 

cotton-boll,  258 
dark-sided,  85 
dingy,  87 
glassy,  88 
granulated,  88 
greasy,  85 
well-marked,  87 
Cutworms,  84,  332 
Cydia  pomonella,  624 
Cylas  formicarius,  438 
Cymatomorpha  riberia,  488 
Cynipidi?,  468 

Dasyneura  leguminicola,   212 
Datana  ministra,  613 
Davis,  G.  C,  342 

J.  J.,  164 
Dean,  Geo.  A.,  199 
Deilephila  lineata,  247,  528 
Depressaria  heracliana,  417 
Dermestida',  474 
Desmia  funeralis,  523 
Diabrotica  longicornis,  157,  159,  160 

duodecimpunctata,  158 

vittata,  303,  379 
Diamond-back  moth,  366 
Diaphania  hyalinita,  400 

nitidalis,  397 
Diastrophus  nebulosus,  468 
Diatra?a  zeacolella,  172,  181 
DicjTihus  minimus,  226 
Dictyophorus  reticulatus,  101 
Diplosis  tritici,  145 
Disonj'cha  triangularis,  335 

xauthomelsena,  335 


Doane,  W.  R.,  330 
Dodge,  C.  K.,  373 
Dolerus  arvensis,  143 
Drasterius  elegans,  82 
Drone-fly,  13 
Dusting  api)aratus,  77 
arsenicals,  44 
Dyar,  H.  G.,  557 
Dysdercus  sutureUus,  253 

Ear-worm,  corn,  181,  235 

Elachistida^,  618 

Elaterida>,  81 

Eliot,  Ida  M.,  525 

Empusa  aphidis,  325 

Enarmonia  interstinetana,  216 
prunivora,  628 

English  grain-louse,  147 

Ephestia  kuehniella,  190 

Epicauta  pennsylvanica,  344 
vittata,  107,  343 

Epidapus  scabies,  300 

Epilachna  borealis,  391 

varivestis,  315 

Epitrix  cucumeris,  296 
fuscula,  296,  299 
parvula,  222,  298,  299 

Epochra  canadensis,  490 

Eriocampoides  limacina,  642 

Erioi)h3'es  pyri,  636 

Eriophj'idse,  636 

Eri.stalis  tenax,  13 

Erotylida:",  202 

Estigmene  acrsea,  247 

Eulecanium  nigrofasciatum,  654 

Euproctis  chrysorrhea,   558 

European  grain-aphis,  604 

Euschistus  punctipes,  225 
variolarius,  225 

Eutettix  tenella,  339 

Euthrips  nicot  anise,  240 

Evergestis  rimosalis,  363 

Exorista  flavicauda,  107 
leucaniae,  107 

Extension  rods,  74 

Fall  army  worm,  118,  247 


676 


INDEX 


Fall  oankcrworm,  572 
wcbworm,  553 

False  chinch-bug,  339 

Farm  methods  for  insect  control,  32 

Felt,  E.  P.,  501,  588,  60S 

Feltia  subgothica,  87 

Fernald,  C.  H.,  563 
H.  T.,  83 

Fertilization,  35 

Fidia  cana,  503 

viticida,  501 

Fire-bug,  368 

Fiske,  W.  F.,  611 

Fitch,  Asa,  132,  146,  318,  320 

Flat-headed  apple-tree  borer,  591 

Flea-beetles,  34,  335,  375 
banded,  402 
cucumber,  296 
eggplant,  299 
grapevine,  515 
pale-striped,  402 
potato,  296 
southern  potato,  296 
spinach,  335 
sweet-potato,  430 
tobacco,  222,  296,  299 
wavy-striped,  375 
western  cabbage,  375 

Flesh-fly,  107 

Fletcher,  James,'  129,  133,  307,  329 

Flf)ur  moths,  189 

moth,  Mediterranean,  189 

Folsom,  J.  W.,  200,  205,  214,  217,  322 

Forbes,  S.  A.,  79,  123,  157,  164,  169, 
170,  175,  177,  330,  335,  402,  413, 
441,  447,  576 

Forbush,  E.  H.,  563 

Foreign  grain-beetle,  188 

Forest  insects,  5 

Foster,  S.  W.,  628 

Four-lined  leaf -bug,  481 

Fruit-fly,  cherry,  667 

Fruits,  insect  injury  to,  4 

Fruit-tree  bark-beetle,  544,  653 

Fruit-worm,  tomato,  181 

Fungus,  grasshopper,  112 
pea-aphis,  325 


Ciall-maker,  grape-cane,  509 
blackberry,  468 
Garden  webworm,  247,  406 
Garman,  H.,  135,  225,  296,  301,  347, 

367,  447 
Gases,  42,  57 
Gelechiida;,  192,  650 
Geometrida;,  488,  570,  572 
German  grain-aphis,  148 
Gillette,  C.  P.,  47,  315,  338,  383,  582 

597,  602,  606,  655,  658,  660,  666 
Girault,  A.  A.,  645 
Girdler,  grape-cane,  511 
Gipsy  moth,  5,  563 
Glassy-winged  sharpshooter,  249 
Goff,  W.  H.,  352 
Goldbugs,  432 
Golden  tortoise-beetle,  435 
Good,  James,  47 
Goodwin,  W.  H.,  474 
Gossard,  H.  A.,  137,  218,  530,  546 
Gouger,  plum,  661 
Graphops  pubescens,  448 
Grain-aphis,  European,  604 
German,  148 
-beetles,  187 

foreign,  188 

red,  or  square-necked, 

188 
saw-toothed,  187 
-moth,  Angumois,  192 
S])henophorus,  175 
Grains,  small,  insects  of,  121 
stored,  insects  of,  186 
Grain  weevils,  186 
Granary,  196 

weevil,  186 
Grape-berry  moth,  530 
cane-borer,  513 

gall-maker,  509 
girdler,  511 
curculio,  534 
leaf-folder,  523 

-hopper,  520 
root-worm,  501 

imported,  504 
-vine  flea-beetle,  515 


INDEX 


677 


Grape-vine  hog-caterpillar,  528 
phylloxera,  492 
root-borer,  497 
Grasshoppers,  93.     See  Locusts. 

southern  lubber,  101 
Grass  moths,  162 

root-louse,  167 
Gray  hair-streak  butterflj-,  319 
Green-bug,  150 
Greenhouse  leaf-tyer,  409 
Green  peach-aphis,  375,  658 

soldier-bug,  252 
Grouiul-beotles,  14,  117 
fiery,  15 
murky,  1(5,  295 
GryllidiV,  464 
Gymnonychus  api)endiculatus,  487 

Hadena  devastatrix,  88 

Haltica  chalybea,  515 

Hammar,  A.  G.,  501,  618 

Harlequin  cabbage-bug,  40,  368 

Harpalus  caliginosus,  16,  295 

Harpiphorus  maculatus,  450 

Hart,  C.  A.,  330,  413 

HartzeU,  F.  Z.,  492,  501 

Harvey,  F.  L.,  490,  632 

Hawk-moth  larvae,  525 

Hay,  insect  injur)'  to,  3 

Headlee,  T.  J.,  379 

Heart,  30 

Hehothis  obsoleta,  24,  181,  234,  254 

Hellebore,  47 

Hellula  undalis,  365 

Herrick,  G.  W.,  371 

Hessian  fly,  2,  34,  40,  123 

Hinds,  W.  E.,  198,  241,  261,  268 

Hippodamia     convergcns,     10,    296, 

385 
Hodgkiss,  H.  E.,  547,  636 
Homalodisca  triquetra,  249 
Honey-bee,  22 
Hooker,  W.  A.,  240 
Hopkins,  A.  D.,  5,  300,  54§ 
Hop  insects,  274 

louse,  275,  664 

merchants,  280 


Hopi)erdozers,  109 
Hop-plant  borer,  273 

plant-louse,  275,  664 
-vine  snout-moth,  279 
Hornblowers,  230 
Hornworms,  228 
Hose,  75 

Houghton,  C.  O.,  464,  616 
Houser,  J.  S.,  136,  530 
Howard,  L.  O.,   112,  175,  222,  234, 

239,  273,  558,  563 
Hubbard,  H.  G.,  246 
Hungate,  J.  W.,  371 
Hunter,  S.  J.,  155 
Hunter,  W.  D.,  3,  94,  19S,  241,  2()1, 

266,  662 
Hyalopterus  arundinis,  662 
Hydrocyanic-acid  gas,  57 
Hj'droecia  immanis,  273 
Hj'lastinus  obscurus,  200 
Hypena  humuli,  279 

rostralis,  280 
Hyphantria  cunea,  553 
textor,  557 
Hypsopygia  costalis,  219 

Ichneumon-flies,  17,  616 
Ichneumonida',  17,  616 
Imported  cabbage  webworm,  365 
ciUTant-borer,  477 
worm,  486 
grape  root -worm,  504 
onion  maggot,  420 
Indian-meal  moth,  191 
Injury  by  insects,  1 
Insecticides,  42 

contact,  42,  48 
poisons  or  ar.senicals,  42 
Isosoma  grande,  138 
tritici,  136 

Janus  integer,  478 
Jarvis,  C.  D.,  616 
Jassidaj,  249,  520 
Jeime,  E.  L.,  624 
Johnson,  Fred,  501,  518 

W.  G.,  58,  190,  224,  326 


678 


INDEX 


Jones,  C.  R.,  254 
Jones,  P.  R.,  628 

Kedzie  formula,  44 
KeUy,  E.  O.  G.,  178 
Kerosene,  49 

emulsion,  48 

Lachnosterna,  79,  415 

arcuata,  80 
Ladybird  beetle,  9,  543 
bean,  315 

convergent,  10,  296 
nine-spotted,  9 
spotted,  11 
squash,  391 
two-s]iotted,  10 
Languria  mozardi,  202 
Laphygma  exigua,  334 

frugiperda,  118 
Larger  cornstalk-borer,  172,  181 
Larva,  23 
Lasiocampida?,  608 
Lasioderma  serricorne,  239 
Lasius  niger  americanus,  165,  168 
Lawrence,  W.  H.,  459,  469 
Leaf -aphis,  corn,  170 
Leaf-beetle,  bean,  313 

three-lined,  303 
Leaf -bug,  cotton,  251 

four-lined,  481 
Leaf-folder,  grape,  523 
-hopper,  grape,  520 
cotton,  250 
-miner,  apple,  616 

tobacco,  237 
-roller,  strawberry,  452 
"tyer,  celery  or  greenhouse,  409 
-weevil,  clover,  203 
Leather]  ackets,  171 
Lebia  grandis,  16 
Lema  trilineata,  303 
Lepidosaphes  ulmi,  592 
Leptinotarsa  decemlineata,   291 
Leptoglossus  oppositus,  252 
Lesser  apple-worm,  628 
peach  borer,  645 
Leucania  unipuncta,  114 


Ligyrus  gibbosus,  414 

Lime-sulfur  wash,  boiled,  50 

home-made  con- 
centrated, 51 
self-boiled,  53    • 

Limneria  fugitiva,  616 

oedemasiaj,  616 

Lindeman,  420 

Liparidaj,  558,  563 

Live-stock,  insect  injury  to,  6 

Lixus  concavus,  408 

Locust,  American  acridium,  99 

California  devastating,  99 
differential,  99,  100 
lesser  migratory,  98 
migratory,  93 
pellucid,  99 
red-legged,  98,  99 
Rocky  mountain,  93 
seventeen-year,  548 
two-striped,  99 
see  also  grasshoppers. 

London  purple,  43 

Lowe,  V.  H.,  472,  484,  608,  618 

Loxostege  similalis,  247,  406 
sticticalis,  332 

Lugger,  ().,  293,  321,  477,  486,  525 

Lyca^nida;,  248,  319 

Lydella  doryphorse,  294 

Lygajidse,  89 

Lygus  pratensis,  339,  404 

Lygocerus  stigmatus,  445 

Lysiphlebus  testaceipes,  154,  385,  445 

Macrobasis  unicolor,  316,  343 
Macrofhictylus  subspinosus,  518 
Macrosiphum  cerealis,  147 
granaria,  147 
pisi,  211,  322 
Maize  bill-bug,  178 
Malacasoma  americana,  608 
Mally,  F.  W.,  418,  451 
Mandibles,  27 
Marlatt,  C.  L.,  1,  7,  121,  143,  209, 

486,  492,  513,  538,  540,  547.  582, 

639,  642,  650 
Maxillae,  27 


INDEX 


679 


Mayetlola  dostructor,  123 

Meadow-maggots,  121 

Meal  snout-nioth,  192 

Mealy  i)liun-louse,  (562 

Measuring  worms,  ^^7() 

Mediterranc^au  flour-moth,  189 

Mcgilla  maculata,  11,  385 

Melanoplus  atlantis,  98 

bivittatus,  99 
devastator,  99 
differentialis,  99,  100 
femur-rubrum,  98 
spretus,  93 

Melanotus  communis,  83 
cribidosus,  82 

Melittia  satyriniformis,  393 

Meloidffi,  301,  316,  343 

Melon-aphis,  241,  383 

Melon  caterpillar,  400 

Membracida;,  547 

Memythrus  polistiformis,  497 

Meromyza  americana,  132 

Metamorphosis,  complete,  23 
incomplete,  26 

Meteorus  hyphantria^  556,  557. 

Mexican  cotton  boll  weevil,  261 

Microgaster,  18 

Micro weisea  misella,  543 

Midge,  clover-seed,  212 

Migratory  locust,  93 

Miscible  oils,  50 

Mite,  locust,  105,  106 

Monophadnus  rubi,  472 

Monostegia  ignota,  451 

Monoxia  puncticollis,  337 

Morgan,  A.  C,  222 

H.  A.,  101,  112 

Morrill,  A.  W.,  252 

Mottled  tortoise-beetle,  436 

Mouth-parts,  biting,  27 

of  plant-louse,  29 
sucking,  28 

Murgantia  histrionica,  368 

Myiarchus  crinitus,  501 

Myzus  cerasi,  666 

persicse,  374,  658 
ribis,  484 


Native  currant  worm,  487 
Nephelodes  minians,  86 
Newell,  Wilmon,  269,  272 
Nezara  hilaris,  252 
Noctua  clandcstina,  87 
Noctuida^,   84,    114,    118,    181,    234, 
243,  254,  258,  279,  287,  334,  361, 
413,  613,  615 
Nozzles,  72 

Bordeaux,  74 

disk,  73 

Vermorel,  72 
Nymph,  26,  550 
Nymphalida;,  280,  283 
Nysius  angustatus,  339 

Oberea  bimaculata,  462 
CEcanthus  niveus,  464 
Oil-and-water  spray,  49 
O'Kane,  W.  C,  632 
Oncometopia  lateralis,  250 
undata,  250 
Onion-maggot,  barred-winged,  423 
imported,  420 
thrips,  418 
Ophion  macrurum,  18 
Orchard  fruits,  insects  of,  538 
Osborn,  H.,  218,  318,  418 
Oscinis  variabilis,  134 
Ox- warble,  6 
( )yster-shell  scale,  592 

Pachynematus  extensicornis,  143 
Pachyi-rhinis  spp.,  121 
Packard,  A.  S.,  613,  615 
Paleacrita  vernata,  570 
Pale-striped  flea-beetle,  402 
Pandorus  sphinx,  527 
Papaipema  nitella,  287 
Papilionidse,  411 
Papiho  polyxenes,  411 
Parasites,  insect,  17 
Paris  green,  43 
Parrott,  P.  J.,  636 
Parsnip  webworm,  417 
Pea-aphis,  34,  211,  322 
insects,  305 


680 


INDEX 


Pea-moth,  328 

-weevil,  305 
Peach-aphis,  black,  655 
green,  658 
borer,  645 

lesser,  645 
lecaniuni,  654 
-tree   bark-beetles,  653 

borer,   California,  645 
twig-borer,  650 
Pear  insects,  582 

-leaf  blister-mite,  636 
psylla,  639 
slug,  642 
Pegoiryij^  brassicse,  347 
ceparum,  420 
fusciceps,  320 
vicina,  345 
Pemi)higius  betoe,  330 
Pentatomidu",  225,  252,  368 
Pergande,  Th.,  147,  418,  604 
Peridromia  saucia,  85 
Periodical  cicada,  548 
Persian  insect  powder,  55 
Petroleum,  crude,  49 
Pettit,  R.  H.,  423 
Phlajotribus  liminaris,  653 
Phelegethontius    quinquemaculata, 
228 
sexta,  228 
Phly('t;enia  rul)igalis,  409 
Pholiis  achemon,  526 
pandonis,  527 
Phorbia  rubivora,  469 
Phorodon  liumuli,  275,  664 
Phthorima>  oi)ei'culella,  237,  289 
Phyllotreta  pusilla,  375 
sinuata,  375 
Phyllotreta  vittata,  335,  375 
Phylloxera  vastatrix,  492 
Physapoda,  418 
Phytonomus  murinus,  205 

punctatus,  203 
Pickle-worm,  397 
Pierce,  W.  D.,  268 
Pierida^,  355,  360,  361 
Pimpla  conquisitor,  243,  246 


Pinii)hi  inquisitor,  17 
Piper,  C.  v.,  651 
Pipiza  radicans,  14 
Pistol  case-bearer,  618 
Plant-bugs,  252 

tarnished,  339 
Planting,  time  of,  34 
Plant-lice,  241,  see  aphides  and  ajihis 

apple,  597 
Plant-louse,  hop,  664 

mouth-parts,  29 
Plodia  interpunctella,   190 
Plowing,  late  fall,  38 
Plum  aphides,  662 
curcuUo,  576 
gouger,  661 
louse,  mealy,  662 

rusty-brown,  665 
Plusia  simplex,  413 
Plutella  maculipennis,  366 
Podisus  spinosus,  293 

spp.,  611 
Poecilocapsus  lineatus,  481 
Poisons,  42 

Polychrosis  viteana,  530 
Polygonia  comma,  281 

interrogationis,  280 
Pontia  napi,  361 

l)rotodice,  360 
rapa',  355 
Popcno.',  E.  A.,  311 
('.  H.,  371 
I'ortlictria  dispar,  563 
l'()l;it(>  insects,  285 

beetle,  Colorado,  291 
scab  and  insects,  300 

-gnat,  300 
stalk-borer,  285 
tuber-worm,  289 
Potherb  butterfly,  361 
Proctotrypida?,  19 
Prodenia  ornithogalli,  258 
Psila  rosse,  415 
Psylla,  pear,  639 
Psylla  pyricola,  639 
Pteronus  ribesii,  486 
Ptinida;,  239,  513 


INDEX 


681 


Pumps,  barrel,  63 

bucket,  60 

horizontal,  67 

knapsack,  61 

power  outfits.  69 

see  also  si)rayers. 
Pupa,  24 
Puparium,  25 
PyralididiP,    190,    191,  192,  219,  247, 

363,  365,  409,  523 
Pyralis  farinalis,  191 
Pyraustidffi,  332,  397,  400,  406 
Pyrethrum,  55 
Pj^rrhocoridtr,  253 

Quaintance,  A.  L.,  78,  228,  236,  241, 
254,  379,  397,  400,  418,  441,  492, 
501,  523,  570,  576,  578,  592,  595, 
597,  608,  616,  624,  628,  632,  645, 
650,  652,  655 

Quayle,  H.  J.,  492 

Railroad  worm,  632 
Raspberry  insects,  459 

Byturus,  474 

cane-borer,  462 
-maggot,  469 

root-borer,  459 

saw-fly,  472 
Red-bug,  253 

Red-humped  apple-caterpillar,  615 
Red-necked  cane-borer,  466 
Red-  or  squaie-necked  grain-beetle, 

188 
Reeves,  G.  I.,  139 
Repellants,  42,  56 
Resin-soap  sticker,  46 
Respiration  of  insects,  28 
Rhagoletis  cingulata,  667 

pomonella,  632 
Rhopalosiphum  dianthi,  658 

ribis,  484 
Rhubarb  curculio,  408 
Rice- weevil,  186 

Riley,  C.  V.,  94,  143,  277,  285, 
294,  371,  375,  406,  417,  437,  452, 
664 


Roberts,  I.  P.,  128 

Root-aphis,  beet,  331 

Root-borer,  clover,  200 

grai)evine,  497 
raspberry,  459 
sweet-potato,  438 

Root-louse,  strawberry,  441 

Root  maggots,  41 

Root-worm,  grape,  501 

strawberry,  448 

Rose  bugs,  518 

Rose-chafer,  518 

Rosy  apple-aphis,  602 

Rotation  of  crops,  33 

Round-headed  apjjle-tree  borer,  588 

Rusty-brown  plum-louse,  655 

Salt-marsh  caterpillar,  247 
Sanborn,  C.  E.,  387,  665 
Sanders,  J.  G.,  654 
Sanderson,  E.  D.,  241,  320,  322,  406, 
430,  441,  558,  563,  597,  602,  613, 
615,  624 
San  Jose  scale,  4,  48,  538 
Sanninoidea  exitiosa,  645 

opalescens,  645 
Saperda  Candida,  588 
Sarcophaga  carnaria,  107 
Saw-fly,  raspberry,  472 
strawberry,  450 
sweet-potato,  437 
western  grass-stem,  130 
wheat,  142 
•Saw-toothed  grain-beetle,   187 
Scale,  oyster-shell,  5V)2 
San  Jose,  538 
scurfy,  595 
terrapin,  654 
Scarabaeida;,  79,  415,  518 
Schistocerca  americana,  27,  99 
Schizocerus  ebenus,  437 

privatus,  438 
Schizoneura  lanigera,  582 
panicola,  167 
Schizura  concinna,  616 
Shoene,  W.  J.,  347,  636 
Sciara,  spp.,  300 


682 


INDEX 


Scolytidae,  200,  544,  653 
Scolytus  rugulosus,  544 
Scott,  W.  M.,  54,  365 
Screw-worm  fly,  6 
Scurfy  scale,  595 
Seed-corn  maggot,  320 
Semasia  nigricana,  328 
Semicolon  butterfly,  280 
Sesiida;,  393,  459,  477,  497,  645 
Seventeen-year  locust,  548 
Silvanus  sui'inamensis,  187 
Simpson,  C.  B.,  624 
Siphocoryne  aven£e,  604,   607 
Sirrine,  F.  A.,  318,  361,  373,  418,  428 
Sitotroga  cerealella,  192 
Sharpshooters,  248 

glassy-winged,  249 
Sherman,  Franklin,  374 
Slingerland,   M.   V.,    128,   347,   409, 
422,  462,  464,  469,  478,  481,  501, 
515,  520,  530,  618,  621,  639,  641, 
645,  667 
Smith,  J.  B.,  164,  195,  274,  282,  289, 
347,  379,  391,  430,  441,  452,  454, 
456,  459,  460,  466,  518,  597,  645 
Smith,  R.  I.,  198,  368,  379,  397,  400, 

582 
Snout-moths,  162 

hop-vine,  279 
meal,  192 
Snout- weevil,  175 
Snowy  tree-cricket,  464 
Soap,  whale-oil,  50 
Soldier-bugs,  611 

green,  252 
Solenopsis  geminata,  269 
Soule,  Carohn  M.,  525 
Southern  grain-louse,  2,  150 
Sphecodina  abbottii,  530 
Sphecius  speciosus,  553 
Sphenophorus,  175 

cariosus,  178 
maidis,  178 
*      obscurus,  175 
ochreus,  178 
parvulus,  175 
pertinax,  178 


Sphenophorus,  placidus,  178 
robustus,  178 
scoparius,  178         ^ 
sculptihs,  178 
Sphingidse,  228,  247,  525 
Sphinx,  Abbott's,  530 
achemon,  526 
pandorus,  527 
white-hned,  528 
Spinach-aphis,  375 

flea-beetle,  335 
leaf-miner,  345 
Spined  tobacco  bug,  225 
Spiracle,  30 
Split-w^rm,  237 
Sprayers,  see  pumps. 

compressed-air,  62 
gas,  70 
traction,  69 
Spray  rods,  74 
Sirring  cankerworm,  570 
grain-aphis,  150 
Squash-bug,  388 

ladybird,  391 
-vine  borer,  393 
Stalk-borer,  287 

potato,  285 
-worm,  tobacco,  224 
Starnes,  H.  N.,  645,  650 
Stedman,  J.  M.,  404,  450,  576 
Stem-borer,  clover,  202 
Stigmata,  30 
Stink-bugs,  252 
Stone,  J.  L.,  128 

Stored  products,  insect  injury  to,  6 
Strainers,  77 

Strawberry  crown-borer,  447 
insects,  441 
leaf-roller,  452 
root-louse,  441 

-worms,  448 
saw-fly,  450 
weevil,  456 
Striped  cucumber  beetle,  379 
Structure  of  insects,  22 
Suck-fly,  226 
Sugar-beet  webworm^  332 


INDEX 


683 


Sulfur,  54 

dioxid,  58 
Swallow-tail  butterfly,  black,  411 
Sweet-potato  beetle,  two-striped,  433 
flea-beetle,  430 
root-borer,  438 
saw-flics,  437 
Symons,  T.  B.,  654 
SjTianthedon  pictipes,  645 
Syrphidee,  12,  325 
Syrphus  americanus,  14 
flies,  12,  14 
ribesii,  13 
Systena  blanda,  402 

hudsonias,  335 
ttrniata,  335,  402 
Systoechus  oreas,  100 

Tachina  flies,  107,  117 
Tanglefoot,  56 

Tarnished  plant-bug,  337,  404 
Taylor,  E.  P.,  405,  576,  582,. 597,  602, 

652,  658,  660,  665 
Tenebroides  mauritanicus,  188 
Tent  caterpillar,  608 
Tenthredinida?,    143,   437,  450,   472, 

478,  486,  487,  642 
Terrapin-bug,  368 

scale,  654 
Tetranychida>,  209 
Three-lined  leaf-beetle,  303 
Thrips  tabaci,  418 
Thysanoptera,  418 
Tineidse,  237,  616 
Tipula  bicornis,  121 
costalis,  121 
hebes,  122 
TipuUdaj,  121 
Tischeria  malifoliella,  616 
Titus,  E.  G.,  205,  208 
Tmetocera  ocellana,  621 
Tobacco,  as  insecticide,  65 

bug,  spined,  225 

bud  worm,  181 

flea-beetle,  222,  296,  200 

fumigation,  58 

insect  injury  to,  4 


Tobacco,  insects,  222 

leaf-miner,  237 

stalk-worm,  224 

thrips,  240 

worms,  228 
Tomatoes,  insects  of,  285 
Tomato  fruit-worm,  181,  304,  see 

bollworm. 
Tomato-worm,        304,    see    tobacco 

worms. 
Tortoise-beetles,  432 

argus,  436 
black-legged,  434 
golden,  435 
mottled,  436 
Tortricida;,  328, 452, 530,[621,  624,  628 
Towers  for  spraying,  77 
Toxoptera  graminum,  150 
Tracheal  system,  29 
Trap  crops,  40 
Tree-cricket,  snowy,  464 
Tree-hopper,  buffalo,  547 
Trichobaris  trinotata,  285 
Trogositidse,  188 

Trichogramma  pretiosa,  244,  254 
Trombidium  locustarum,  105 
Trouvelot,  Leopold,  564 
Trypetidaj,  490,  632,  657 
Tuber-worm,  potato,  289 
Twelve-spotted  asparagus  beetle,  427 
Twig-borer,  peach,  650 
Tychea  brevicornis,  331 
Tyloderma  fragraria?,  447 
Typhlocyba  comes,  520 
Typophorus  canellus,  448 

Uranotes  mellinus,  248,  319 

Volunteer  plants,  35 

Washburn,  F.  L.,  113,  148,  190,  289, 

347 
Wavy-striped  flea-beetle,  375 
Webster,  F.  M.,  2,  41,  89,  126,  129, 
130,  133,  136,  138,  139,  143,  145, 
147,  155,  157,  164,  169,  202,  205, 
208,  459,  463,  466,  509,  606 


684 


INDEX 


Webster,  R.  L.,  323,  596 
Web  worm-  corn-root,  161 
faU,  553 

garden,  247,  406 
imported  cabbage,  365 
sugar-beet,  332 
Weed,  C.  M.,  371,  388,  666 
Weeds,  34 
Weevil,  186 

alfalfa,  205 
destruction  of,  197 
Mexican  cotton  boll,  261 
strawberry,  456 
Western  corn  root-worm,  2,  33 
grass-stem   saw-fly,    130 
Whaleoil  soap,  50 
Wheat  joint-worm,  37,  136 


Wheat  maggots,  132 

midge,  145 

saw-flies,  142 

saw-fly  borer,  129 
-stem  maggot,  132 

straw-worm,  138 
White  grubs,  79,  332 
White-Hned  sphinx,  247,  528 
Wilson,  H.  F.,  653 
Winthemia  4-pustulata,  117 
Wire  worms,  81,  332 
Woglum,  R.  S.,  543 
Woolly  apple  aphis,  582 
Woolly-bear  (caterpillar,  247 
Woodworth,  C.  W.,  543,  645 

Yellow-necked  apple-caterpillar,  613 


PR< 


METCAUF 


^.r^lfcV 


